HAN Select Options_Supporting Document_Stage 12

Industry’s Draft Technical Specifications

Supporting Document

HAN Select Options

SMDG Working Group HAN Working GroupOriginal Author Simon HarrisonHothouse author Simon HarrisonReviewed by Hot House Group 3

Version Date Author Description Version 1.0 4/8/11 Programme Baseline version uploaded to huddle. The

baseline was set at the time Industry’s Draft Technical Specification was published.

This document was drafted by industry. It has not been reviewed formally by the Department of Energy and Climate Change as part of the Hot House 6-week Process. Consequently, the wording and structure of this document are exclusively from industry.

HAN WG - RecommendationsDoc Ref: HANWG.08

By HAN Working Group

Contents

1Overview ...................................................................................................................................................................... 4 2Document Control ....................................................................................................................................................... 4 3Disclaimer .................................................................................................................................................................... 4 4Glossary & Definitions ................................................................................................................................................ 4 5Executive Summary .................................................................................................................................................... 5 6Introduction ................................................................................................................................................................. 6 7Group Activities ........................................................................................................................................................... 6 8SMHAN specific terminology ..................................................................................................................................... 8 10Design Assumptions ............................................................................................................................................... 10 11Making a HAN Decision .......................................................................................................................................... 12 13HAN Technologies ................................................................................................................................................... 15 15Further Considerations ........................................................................................................................................... 15 32HAN Evaluation Criteria .......................................................................................................................................... 36 34Conformance Testing of Directly Connected SMHAN Devices ........................................................................... 37 Appendix A - HAN Evaluation Exercise ..................................................................................................................... 40 Appendix B - HAN Testing Exercise Report .............................................................................................................. 41 Appendix C - HAN ESoDR– Evaluation Criteria ........................................................................................................ 43

1 OverviewThis paper is a deliverable produced by the HAN WG. It describes the activities of the group and collects materials produced by the group. Where appropriate it presents options and recommendations to the Programme related to the use of HAN technologies to support smart metering.

2 Document ControlVersion Date Author Description

0.1 12/5/11 Simon Harrison

Initial Draft


Updated before meeting #14


Update following meeting #14


Update ahead of final HAN WG meeting


Update following final HAN WG meeting

Distributed to HAN WG attendees


Further iteration following final HAN WG meeting


Update for Hothouse review


Update to Appendix B

3 DisclaimerThis document presents options relating to the operation of smart metering in Great Britain. The options presented do not represent all possible solutions. We have used reasonable endeavours to ensure the accuracy of the contents of the document but offer no warranties (express or implied) in respect of its accuracy or that the proposals or options will work. To the extent permitted by law, the Energy Retail Association and its members and any members of the HAN Working Group do not accept liability for any loss which may arise from reliance upon information contained in this document. This document is presented for information purposes only and none of the information or options presented herein constitutes an offer.

4 Glossary & DefinitionsFor consistency with other deliverables from the HAN WG and other working groups, the terms and definitions used in this document comply with the SMDG glossary maintained online during the development stage of the Programme.The glossary can be viewed here:https://sites.google.com/site/smdgsg1/smdg-glossary

https://sites.google.com/site/smdgsg1/smdg-glossary

5 Executive SummaryThis document presents considerations and recommendations for a number of issues associated with the concept of a Home Area Network (HAN) for smart metering. It has not been possible to reach conclusions on all of the issues discussed by the HAN WG, indeed some issues would require extensive real world testing or ‘on the job’ learning to resolve definitively.

Wherever possible, the HAN WG has provided options relating to these issues and recommendations against these options.

As presented in detail below, the HAN WG has adopted an approach of clarification and specification, rather than selection, throughout its work. Acknowledging that the most immediate challenge from the Programme and industry with regard to a Smart Metering HAN (SMHAN) is finding options that work effectively and interoperably today, it remains the case that;

- There are no convincing ‘obvious’ answers on technologies; even the market leaders are relatively ‘immature’, or have key ‘gaps’ in their specification

- Technology options are constantly developing (in terms of performance and interoperability), with the potential for improved and better options to arrive very quickly

- The evidence base, particularly for wired HAN options, is extremely limited.

Therefore the working assumption of the HAN WG has been to provide guidance on evaluating HAN technologies, and the main recommendation is that the Programme utilises the Evaluation Criteria and Tests developed by the group (see Appendix) to support either;

- A specification and ‘fit for purpose’ assurance regime on an on-going basis, or- A selection process undertaken by the Programme or under Industry auspices, to determine the most

suitable HAN technology ‘set’ to deliver HAN connectivity for GB.

These options are not necessarily mutually exclusive. Any initial ‘fitness for purpose’ assurance assessment could also serve as a selection process, and the on-going testing for new technologies (including interoperability fit with existing) would ensure that the smart metering door remained open to new solutions where appropriate.

What is exceptionally clear is that further testing is needed, and evidence needs to be gathered to cut through claims, assumptions and marketing blurb. It is the view of the HAN WG that any testing regime needs to include field tests of both wired and wireless HAN solutions in a range of GB meter locations, particularly those viewed as ‘difficult’.

The HAN WG has spent considerable time challenging some of the common perceptions of HAN solutions, or the issues they will encounter. Whilst some myth busting has been possible, there is a concern that this might be knowledge that is limited, or could be transitory, unless it is appropriately acknowledged and embedded within published Programme documents and developed further in planned activities that follow this piece of work.

In particular, the key issues remain in the minority cases – for example, where the gas meter is in a difficult position, or where the system has to work in high-rise buildings – and these issues are as much about

perception as they are about fact. Similarly, the presumed resolution of these issues – use of a wired solution, use of a different radio – remain unproven assumptions. In order to remove the uncertainty, more information on potential wired solutions is needed, and testing of both wired and wireless options is required.

From the work of the group, in line with the work of the Difficult Meter Positions WG, it would be reasonable to assume that 70-80% of premises can be served by one or more wireless technologies, and that a variety of infill technologies or equipment could be used to deliver connectivity for the remainder.

The main issue encountered by the group was that the HAN remains a relatively immature use of new technologies – there is little evidence globally of large-scale deployments to call upon on. Decisions made in other implementations appear to have been made mainly on paper-based assessment processes, and in market structures that do not apply the key interoperability stress test that the GB energy market places on metering components.

However, our informal evaluation exercise (see Appendix A) has shown that there are options for the main wireless SMHAN technology, and that these options could be aligned with the GB requirements within the proposed time constraints. A number of members of the HAN WG support that the next step should be a selection process, and then work with ‘selected’ technologies to deliver assurance and confidence in performance and interoperability. Other members feel that it is not necessary for the selection to be done by the Programme, as the GB market is currently working towards a market leader independently of the Programme.

The key recommendations of the HAN WG are:- To utilise the Evaluation Criteria and Tests attached to this document as a proposed enduring

appendix to the ESoDR – either for a specification regime or selection activity- Clarification from the Programme on specification and/or selection would resolve some of the

ambiguity in this critical area and allow for clear planning on the next steps- To undertake ‘real world’ testing of HAN technologies very soon, and to gather evidence from early

implementations, to inform the Evaluation Criteria documentation and ensure it is fit for purpose- Build on the initial foundation of lab testing done by the HAN WG by undertaking a more

substantial research and ‘real world’ testing activity, specifically including powerline technologies- The Programme needs to resolve the issue between robustness and coverage, in order to determine

what types of hardware can be used for difficult meter positions- Further paper-based investigation could be done on technical issues such as antenna design

recommendations, a detailed security assessment of suitability and practicality, and other issues that would not fundamentally change/alter any key technical requirements.

6 IntroductionThis paper forms the final deliverable of the HAN Working Group. It describes the work of the group, collects the material produced by the group – in particular the proposed HAN schedule to the ESoDR – where appropriate, presents options and recommendations to the Programme.

7 Group ActivitiesThe HAN Working Group met on 16 occasions between February and June 2011. Participating members of the group were drawn from across industry and included:

- Meter manufacturers- Silicon vendors- Communications experts- Radio experts- Security experts- Energy retailers- Non domestic participants- Government and regulatory participants

A wider distribution list, of over 50 members, were ‘papers only’ participants providing review and comment and included solution providers, experts and interested parties from across Europe, America and Asia. The HAN WG received a number of valuable contributions from this wider distribution list and would like to put on record its thanks to all who contributed in writing and in person to the work of the Group.A key element of the work of the HAN WG was to ensure consistent design and development work with the peer SMDG working groups – some key highlights have been:

The HAN WG initially worked closely with the Architectures WG to review and inform the high-level architectures for the SMHANThe HAN WG shares a number of members with the Difficult Meter Positions WG, and both groups have aligned their activities to take account of each other’s and wider Programme requirementsMembers of the Interoperability Testing WG have joined the HAN WG for a number of sessions, with a particular view to understanding how HAN testing and certification may be deployed on an on-going basis

The group was charged with producing HAN evaluation/selection criteria to support the relevant ESoDR requirements, and yet to be developed architectural and security requirements. The appendix to this document reflects a successful delivery against this target.

The group produced a number of documents to support this final deliverable, and others which served a purpose to advance issues and understanding. All of the papers for meetings, outputs from the group and related materials can be viewed at the group website - https://sites.google.com/site/smdghanwg

The group undertook an informal evaluation and testing exercise to assist with raising the profile of the GB requirements, and to gauge the practicality and suitability of the draft Evaluation Criteria. An appendix to this document describes the exercise and the results.

The figure below highlights the overall flow of the work within the group on the key Evaluation Criteria deliverable:

https://sites.google.com/site/smdghanwg

Eval Testing

Security Reqs

ESoDR

Evaluation Criteria

Evaluation Exercise

Adjust/ Update Evaluation

Criteria

Recommend Performance & Non Func Req’s

Add detail to HA req’s in ESoDR

Refer to ESoDR HAN Schedule

Existing & Updated high level functional requirements

Functional requirements expressed in real world context for evaluation

Technology Suitability

Some

and/or

NoneAll

Assess Options & Gaps

Issues OptionsAs might be addressed by amending requirements Next Steps

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Figure HAN WG Activity

8 SMHAN specific terminologyThe HAN WG has developed definitions for a number of key terms throughout its work. It recommends that these terms are included in the ESoDR glossary. The following paragraphs summarise these terms and explain their meaning and use.

8.1 SMHAN Device Classes

A number of classes of Device have been defined. The definitions are:

Approved SMHAN Device An Approved SMHAN Device has been Approved for direct connection to the UK SMHAN. It will be identified with an approval Mark.

Authenticated SMHAN Device An Approved Device that has been authenticated for attachment to a specific SMHAN.

Active SMHAN Device An Authenticated Device that is currently operating on a specific SMHAN.

Detached SMHAN Device An Approved Device that formerly was authenticated, but has had this authentication removed. A Detached SMHAN Device may be re-attached by going through the authentication procedure again.

Gateway SMHAN Device An Approved SMHAN Device which includes an interface to other devices outside the SMHAN (e.g. home energy management systems).

Unapproved Device Any device which is not approved for direct connection to an SMHAN.

The following notes apply to the above Device classes:

• Only Approved SMHAN Devices can be Active on an SMHAN

• Approved SMHAN Devices can be connected to the SMHAN with an Authentication process that is implemented by the system

• A handheld installer terminal is an example of an Approved SMHAN Device that may be Authenticated but subsequently Detached and therefore no longer Active. The terminal would be Authenticated for use whilst installing a customer’s SMHAN, but would then be Detached from that SMHAN on completion of the installation, preventing this Device from becoming Active again on

that SMHAN

• An example of an Authenticated but not Active Device would be an electric vehicle which has been driven away from coverage of the SMHAN for which it is Authenticated

• Unapproved Devices can be connected via a Gateway SMHAN Device which is itself an Approved SMHAN Device. This means that householders are NOT permitted to buy any commercially available HAN device (e.g. a third party energy management system) and connect it directly to the SMHAN, unless it is Approved. This constraint is to protect the SMHAN security

• A set of APIs will be defined and published for Gateway SMHAN Devices, setting out what information is allowed to be written via the Gateway into the SMHAN and read by the Gateway from the SMHAN.

The figure below illustrates the relationship between the Device types described above.

Approved SMHAN Devices Unapproved Devices

Authenticated SMHAN Devices

Active SMHAN Devices Detached SMHAN Devices

Figure Types of HAN Devices

8.2 Other SMHAN Devices

In addition to the main Device classes listed above, two other types of device may be used in some SMHAN installations. These will need to be Approved and Authenticated in order to connect to an SMHAN. The definitions are:

SMHAN Bridge Device An Approved SMHAN Device which passes data between two physically different mediums, providing translation of message formats where necessary.

SMHAN Repeater Device An Approved SMHAN Device which receives an SMHAN signal and retransmits the signal on the same physical medium and network (SMHAN).

The following notes apply to the above Device classes:

• An SMHAN Bridge Device may be used, for example, where physical installation limitations mean that a combination of wired and wireless communication is required to connect Smart Metering System Device to the rest of the SMHAN

• An SMHAN Repeater Device may be used, for example, where a Device to be connected to the SMHAN is too far away (or attenuation is too great) for it to operate reliably when connected directly to the SMHAN

• Note that suppliers have stated that connections via the SMHAN to meters used for billing purposes cannot be subject to easy or inadvertent disconnection by customers. This implies that SMHAN Bridge and Repeater Devices used to connect meters would need to be powered from supply side, or otherwise provided with power that is independent of customer action. Connections to IHD devices should be in the interest of consumers to maintain, and therefore, use of plug-in extenders is permissible

• Other names for SHMAN Repeater Devices include “Boosters”, “Extenders”, “Routers” and “Range Extenders”.

HAN WG Recommendation(s):

9 The HAN WG recommends that these terms, definitions and approaches are part of the wider SMDG and Smart Metering documentation

10 Design AssumptionsThroughout, the HAN WG has worked to a collection of Design Assumptions – these were published to the Programme as an early deliverable.

The design assumptions used by the HAN WG;

• All Smart Metering System Devices shall communicate via the SMHAN and will each require SMHAN hardware to support this

• Each Smart Metering System device shall be capable of being exchanged• The Smart Metering System shall contain a Device which acts as the controller for the SMHAN.

This controller must exist for both wireless and wired HANs although the detailed implementation will differ in each case. The controller will store relevant and appropriate information about the network

• The controller can be considered as a piece of software which runs on an embedded micro controller somewhere in the system, and which has an interface to an SMHAN Device

• The SMHAN is a network communications system that transports messages between the Devices connected to it. The primary responsibility for system functionality will be in the application software resident in the connected Devices

• The SMHAN may also contain some system functionality and will need to interface with application layer software in order to implement all functions. SMHAN system functionality is implementation dependent but could include tasks such as authentication and access control

• The SMHAN is configured to carry messages between connected Devices as determined by configuration and application code resident on Devices within the Smart Meter System

• Access control mechanisms will be built into the system software and hardware to allow message transfer between Devices in an approved manner

• The messages which are transported by the SMHAN may be encrypted for security or privacy reasons

• The SMHAN will support physical layer media of three types: a wireless based system, a power line communications (PLC) system, and a direct wired1 system. Our current assumptions of the relative proportions are:

Figure Illustration of SMHAN Physical Layer Coverage

• As propagation issues will impact the percentage of SMHANs that are purely wireless, some Smart Metering Systems will need to use wired solutions to tackle issues such as tall apartment blocks

• The Smart Metering System application will need to work across the three physical layer media types

• Apart from configuration, the Smart Metering System application should have equivalent features across the three physical layer media types

1 The direct wired system could be electrical or optical.

• The SMHAN will have interfaces to metering Devices and the IHD• All architecture options require an SMHAN• The Smart Metering System allows the connection of Approved Devices to the SMHAN. Examples

of Approved Devices include Generation Meters and Load Control Devices• The Smart Metering System allows the connection of other networks and consumer devices through

Gateway SMHAN Devices, attached to the SMHAN• The SMHAN must coexist with other networks that might be present in the home. These include

WLAN devices (e.g. for broadband connection), powerline devices, and wireless devices that consumers may purchase for energy managementInstallation or test Devices (e.g. used by installers) will also need to be connected to the SMHAN. These will need to be Approved SMHAN Devices.

11 Making a HAN DecisionFrom the outset, the HAN WG has faced the challenge of delivering options to the Programme without the consideration of those options becoming a ‘solution selection’ process. The mandate to the group was to consider all solution options against the requirements and to recommend how the Programme or Industry might subsequently determine the most appropriate technical solution, or combination of solutions.

At no point has the target of the HAN WG been to ‘pick a winner’ – there has not been the time, resource or budget to undertake such a selection with anything approaching the required diligence for technology that will be installed into every home in Great Britain.

The HAN WG presented a paper2 to the SMDG and Design Authority, outlining the approach being taken and the consequences. The assumption of the HAN WG has been endorsed throughout – this assumption has been to produce criteria to sit alongside the ESoDR requirements to increase confidence that individual HAN technology candidates are fit for purpose.

The full paper can be reviewed at the HAN WG internet site – a summary of the content is presented here.

11.1 OptionsWhen discussing a Smart Metering Home Area Network (SMHAN) for GB homes, a fundamental decision needs to be made regarding the selection of standards and technologies to be used in the SMHAN:

• Select a GB SMHAN Standard to work with certain physical media; OR• Publish a GB SMHAN Requirements Specification potentially applicable to multiple standards and

physical media.

Selecting a standard can mean different things to different people depending on the context, so it is important to clarify what we mean by a SMHAN standard and why it is important to be clear about this.

In simpler language:

a) That GB smart metering use the following Standards and Physical Media for the SMHAN: a. WaveBee (a made-up fictitious standard) RF and b. PowerPlug (a made-up fictitious standard) Wired

b) That GB smart metering use SMHAN technologies which meet the following requirementsa. Successful evaluation/certification from TestLab Co. (a made-up, fictitious company) against

the technical and non-technical HAN evaluation criteria documented alongside this recommendation

There are real world (i.e. not technological or interoperability) implications of the two options.

2 HAN WG Decision Options v1.1

https://sites.google.com/site/smdghanwg/home/papers/HANDecisionOptionsv1.1.docx?attredirects=0&d=1

With Option A – a named technology/solution – the main consequence is that the choice between solutions within physical domains is removed. This makes it easier for a customer to purchase devices that will work with the smart metering system in their home – they do not need to know if they have a VHS or Betamax home (or HD-DVD or BluRay, or DVD-R+ or DVD-R-), as every smart metering system connects using WaveBee radios or PowerPlug wired connections.

However, picking a technology now ties all homes to that solution for at least 15 years, possibly longer. It is less than 15 years since VHS was the only ‘sensible’ option for video, which has seen three generations of technology since. There is a risk of obsolescence as a result of picking a standard today – and no-one can know if ‘WaveBee’ will still be relevant in 15 years. At the same time, the ubiquity of smart metering guarantees a market for the technology, and therefore should see it develop harmoniously rather than resulting in SMHAN devices becoming impractical. The risk of a technology that appears viable today becoming irrelevant within the lifecycle of a generation of smart meters remains.

Option A also presents a legal and regulatory concern for the Programme. Making a decision on a particular standard within a Government Programme presents a number of specific challenges that are simply not there if that decision occurs within a commercial market – i.e. sometimes a single solution becomes the defacto standard, as illustrated in the VHS vs. Betamax or BluRay vs. HD-DVD markets.

Option B provides less specific certainty, but could provide some guidance to assist customers and product developers who need customers. Rather than explicitly stating ‘WaveBee’ RF, the recommendation could be for an RF solution that is standards compliant, within a specific frequency band (or bands) if applicable or available, deploying specific security measures and meeting the performance standards set by the Evaluation Process. Any candidate technology would need to be evaluated by an independent certification body before earning the right to mark their products as Type Approved ‘GB Smart Meter Compliant’.

This approach is analogous to the development of the Digital TV market – equipment must be marked as compliant with requirements before it can add the ‘Freeview’ mark – but this is an industry/market activity and not something coming from central Government. However, this development occurred only after the regulator had provided guidance to the industry by recommending that they built on the leading established solution to develop their standard.

We may see developments where products include more than one way for connections to be made – laptops and phones have various physical options, and SMHAN devices might follow suit when WaveBee or Z-Zig radios become as economic as Wi-Fi and Bluetooth radios are now for their particular applications.

The Programme is also a Government activity and the activities and recommendations of the Working Group do not have to be strictly followed by industry (unless reflected in regulations), which could see the market settle on a single solution that meets the HAN WG requirements. The distinction on context between Programme and Industry is significant and should not be lost in the discussion.

Similarly, any Government specification that named individual technologies or versions of technologies could result in some very detailed scrutiny from Europe to ensure standards compliance.

11.2 Impacts of OptionsWhether or not a particular HAN technology (or element of a technology) is specified by the Programme will have an impact on several parties. Some considerations from different stakeholders are shown below.

It is key to note that, in the absence of a universal SMHAN technology (which must be wireless to meet the assumptions for gas meters), any ‘selection’ would include:

• Preferred wireless SMHAN solution, and• Wired SMHAN infill solution, and• Secondary wireless SMHAN infill solution

Several of the assessments presented below are necessarily, and sometimes deliberately, subjective and are simply illustrations.

11.2.1 CustomerAs discussed in an appendix to the HAN WG Decision Options paper, it is perceived that having a single national standardised set of SMHAN technologies would simplify the environment for the customer.

Any SMHAN Gateway, or any other device, service or application seeking to connect directly to the SMHAN, would need to use the selected SMHAN solution.

However, it is important to note that any Consumer HANs may be entirely separate networks that connect to the SMHAN via an Approved Gateway Device – and so knowing what SMHAN the Smart Meter System uses is relevant only when considering the Gateway, which could be a device with wired/wireless ports or on board modularity. Gateway functionality could include redundancy to allow several types of connections, or could be embedded as an additional feature within a device created to perform a different primary function. Therefore, internet routers or set-top boxes could include SMHAN hardware and offer convergence of different services, or Gateway functionality could be embedded in advanced IHDs, or new thermostats – simply by including the necessary SMHAN hardware.

A single standard would make Gateway design and purchases straightforward, but if there are alternative SMHAN technologies, then a customer may need to know what standard is used in their home. The HAN WG does not anticipate this being a particularly long list if there is no mandated option – it should represent the same as ‘petrol or diesel’, ‘PC or Mac’, or ‘Phone Line or Cable’ – but may not be something that all customers remember and they may need to investigate if they decide to purchase a Gateway.

Alongside increasing certainty, and removing any potential confusion, selecting a single standard will also increase the risk to customers if that single standard fails, and they are required to replace or supplement equipment as a result of that ‘single point of failure’. A failure in the successful operation of the chosen SMHAN technology will reflect very badly on the overall implementation of smart metering, as it is one of the areas that customers will actually be involved in.

11.2.2 InstallerIt has been considered that if HAN solutions were selected then the logistical and operational challenge for field work could be lessened. If components only ever use one or two selected technologies, then inventory and diagnostic challenges should be much simpler than if a range of options are available.

A single set of solutions might be restrictive or challenging for an installer at a first implementation of the smart meters – achieving a reliable connection for all devices could be more difficult than if there were an option to use a wider range of ‘fit for purpose’ wireless and wired equipment than might have been mandated.

Finally, any subsequent maintenance work should be simplified for installers and field workers arriving to address issues with smart metering equipment – diagnostic tools, or replacement equipment can all be developed using straightforward assessments about SMHAN hardware.

11.2.3 SupplierFixing the SMHAN options to a specified list should simplify matters for Suppliers – they would not need to consider HAN options when procuring metering equipment, and they could provide customers with advice on HAN issues with certainty about the common techniques that could be used.

A selection of technologies should remove any risk to Suppliers on SMHAN interoperability when customers change Supplier.

However, a single set of options would restrict commercial and technical innovation opportunities for Suppliers to offer ‘something different’, particularly if there are challenging issues for the selected technologies.

11.2.4 ManufacturerMeter manufacturers are leading participants and promoters of HAN technology standards, and therefore should be comfortable with a single solution set they are familiar with. GB trade associations are developing working methods to ensure that ‘manufacturer options’ within technologies do not break interoperability.

Gaining interoperability or conformance testing approval for a single technology should be simpler for a manufacturer, although a risk would remain that this might actually be a bottleneck or additional cost on the industry.

At the same time, meter manufacturers sell into a range of international markets, and need to support a range of HAN technologies within their products. Fixing on one solution for GB might deprive this market of any relevant developments and advances on other platforms within individual manufacturers, or their trade associations.

HAN WG Recommendation(s):12 That the Programme take account of the materials presented by the HAN WG and clarify the next

steps for HAN technologies – specification or selection

13 HAN TechnologiesThe HAN WG identified over 40 potential technologies as being candidates for use in an SMHAN context. It undertook a Request For Information activity with these technologies. The responses and other information are captured in the HAN WG product HANWG.06.

Figure Clipped Extract of HANWG.06 Product

The figure below provides a simplified summary of information relating to technologies which responded to our RFI, and reflects the information provided to the HAN WG and has not been independently verified.

Dash 7

433 MHzISO 18000-1

Wireless options 315 to 433 MHz

FlexNet

~400 MHz

FlexNet

EnOcean

868 MHz(or 315MHz)

EnOcean

OneNet

868 MHz

OneNet

IP500

868 MHz

IEEE 802.15.4

IP500 based on 6LowPAN

Multiple including BACNet

KNX

868 MHz(or PLC)

ZigBee SubGHz

868 MHz

DECTULE

1.9 GHz(or 2.4GHz)

ETSI EN-300 175

DECT networklayer or SEP2.0

similar

Any IP based

ZigBee Pro/SEP1.x

2.4 GHz

IEEE 802.15.4

ZigBee Pro/ SEP1

DLMS / SEP 1.xDLMS tunneling

ZigBee IP / SEP2.x

2.4 GHz

IEEE 802.15.4 or IP

compliant Phy

IPv6

DLMS / SEP 2.x

ZWave

868 MHzZwave Phy

Zwave network

DLMS / AdvancedEnergy Control

FlexNet

FlexNet

DLMS / SEP1.xKNX / MBUS /

EnOcean

EN50090

PhL

KNX / MBUS

IEEE 802.15.4

ZigBee Proat subGHz

in development

To be defined

868 MHz 1.9 GHz 2.4 GHz

PLC G3

3-150 kHz Cenelec(or 10-390 kHz FCC)

OFDM

IPv6

DLMS / SEP2.x

G.hn

0-25MHz

OFDM

IPv4 or IPv6

DLMS / SEP2.x

G.hnem

0-500kHz

OFDM

IPv4 or IPv6

DLMS / SEP2.x

HomePlugGreenPhy

2-30MHz

OFDM

IPv4 or IPv6

SEP2.x

NarrowbandWired PLC options

Broadband

BACNet

Multiple options

BACNet layer

BACNet layer

DNP3

Multiple options

DNP3 data model

DNP3 layer

N-DNet

0-500kHz

HomePlug or wireless 350-950 MHz

Hybridmesh

DLMS / MBUS

Options with no specific or multiplePhysical layer

Figure Overview of Technologies in HANWG.06 Document

HAN WG Recommendation(s):14 That the Programme, and industry, continue to monitor developments in wired and wireless

technologies, as even during the course of HAN WG meetings there were key changes.

15 Further ConsiderationsDuring the work of the HAN WG, a number of key issues were discussed – some related to design considerations, some to security, some to commercial elements. Where these issues were considered suitably important, the WG produced papers explaining the issue and any known options.

Materials from these papers which are relevant are included in this section of the report.

15.1 HAN Variants, including robustness vs. coverage considerationsThe HAN WG has considered the practical implications of attempting to connect Smart Metering System components in every GB premises covered by the Programme. Whilst the overwhelming majority of premises should be served well by existing technology options, a number will require different physical hardware to achieve reliable connection.

As part of the work of the group, a paper was issued to other WGs, seeking their input on the potential issues arising from needing to consider more than one physical layer in a single SMHAN installation.

The HAN WG have assumed a requirement for Wireless and Wired options for a HAN, but also that a wired option is not appropriate for a gas meter, based on recommendations from Suppliers and Manufacturers on the economics of producing a suitably AtEx-rated gas meter for a minority of installations. Of particular concern to the HAN WG is the need to provide a HAN connection to gas meters in challenging locations.

15.1.1 Description of Issue & ConsiderationsIt has been assumed by the HAN WG that low power radio will not be suitable to provide HAN connectivity for all homes in the country, without additional ‘extender’ hardware. Depending on meter location, construction materials, and other factors, it may be necessary for alternative technologies to supplement or replace low power radio.

This paper attempts to illustrate the consequences of this from a HAN hardware perspective only – we are seeking to establish a reliable connection. Economics, logistics, interoperability and other issues are not addressed in detail.

15.2 Coverage vs. RobustnessA number of the scenarios illustrated make use of additional ‘boxes’ to achieve a connection. Whether these be repeaters, extenders or boosters (as supported by requirement HA.9 in the ESoDR), there is a concern that this might be in conflict with requirement OP.1 of the ESoDR – that no part of the infrastructure is reliant upon third parties, including consumers, for ongoing availability.

The issue is that, presently, the current options for range extenders tend to be of the ‘plug-in’ or ‘plug-through’ variety, and therefore at risk of being deliberately or inadvertently turned off by consumers.

Discussions within the HAN WG have distinguished that where equipment being supported by HAN range extenders is used to deliver a perceived customer service/benefit, such as for an IHD, this may be

fundamentally different from where HAN range extenders are required for a core utility service, like the connection to a gas meter.

If a customer unplugs an extender and the effect is that their IHD drops off the SMHAN, this is viewed as an acceptable result of cause and effect. However, OP.1 excludes devices that rely upon the customer to pay their electricity bill – so even hardwired solutions on the consumer mains wiring to support extenders for gas meters are not acceptable. There may be exceptions where there is common/landlord power available as one might expect in public areas of multi-occupant premises.

Whilst plug-in extenders may come equipped with battery backups, this adds cost and only provides a temporary support as range extenders generally need to be mains powered to fulfil their activity satisfactorily.

However, plug-in range extenders are perceived as relatively cheap and interoperable devices, especially compared to the installation cost/disturbance of a hardwired option, or the interoperability issues that might result from having to use a different technology to reach remote nodes, particularly battery operated ones like gas meters.

15.2.1 A Mesh might helpSome of the RF technologies being considered for the HAN are capable of operating as mesh networks. This would reinforce and extend the range of the networks, particularly for multi-occupant premises.

An illustration of how RF could mesh is shown below.

Basement

1st Floor

3rd Floor

2nd Floor

4th Floor

Ground Floor

Figure Illustration of Mesh

However, not all of the technologies being considered support a mesh, there are possible logistical issues with the installation, power and robustness of the mesh points. No wired option supports mesh. The security considerations for mesh solutions have not been discussed.

Most importantly, mesh provides an alternative to a variant using standard RF kit – it does not drive variants, and therefore is not a central consideration.

15.2.2 Description of VariantsEach one of the Variants is illustrated using simple functional block pictures – with the SMHAN hardware described as either ‘RF’ for a radio, or ‘PLC’ for a power line transceiver.

Other conventions are also used:- The DCC could be a third party if a SME customer has elected to unbundle- There are architectures where there is no physical communications hub, or where the hub is

integrated into the electricity meterNeither of these issues is seen as material to the consideration of SMHAN hardware, so a ‘typical’ installation is used to illustrate the position.

A number of these variants may be inconsistent with Programme requirements in the ESoDR (e.g. Variant 2a and OP.1), or the agreed architectures, but are included for completeness of the assessment of options.

No assumptions have been made about radio performance, propagation, connectivity or interoperability – it simply deals with the hardware implications of needing to provide HAN connectivity to all Smart Metering System components.

It is expected that each of the physical hardware options is capable of transporting a common application layer – i.e. that the same data items, security and message protocols can be used over radios and wires within the same SMHAN network context.

Whilst the HAN WG Design Assumptions allow for a dedicated wiring option for circumstances where neither RF or PLC are suitable, this is believed to be an option that will be used in an absolute minimum of sites, and no further detail is addressed here.

Standard: All WirelessAnticipated to be suitable for the majority of smart meter implementations. This model includes a SMHAN radio in each of the Smart Metering System components.

Comms HubRF

Elec Meter Gas Meter

IHD

RFRF

RF

WANDCC

Figure Standard Installation

Variant 1a: Hybrid Comms Hub to Wired IHDUnder this variant, as might be found where metering equipment is remote from dwelling quarters – i.e. in multiple occupant properties, the Comms Hub includes a SMHAN Radio and a SMHAN PLC transceiver. The PLC connection utilises mains wiring to reach an IHD unit with a suitable PLC transceiver.

Comms HubPLC RF


IHD

RFRF

WANDCC

PLC

Figure Variant 1a

The implications of this variant:• Hybrid Comms Hubs need to be available to use at installation• PLC IHDs need to be available to use at installation, increasing the number of IHD variants• Customer needs to be aware that their IHD connects via PLC and not RF• There may be particular security issues with data on PLC layer ‘leaking’ beyond the property

Variant 1b: Hybrid Comms Hub to Wired Electricity MeterUnder this variant, similar to 1b, it is the electricity meter which requires a PLC connection to the Comms Hub.

Comms HubRF


IHD

RFRF

RF

WANDCC

PLC

PLC

Figure Variant 1b

The implications of this variant:• Hybrid Comms Hubs need to be available to use at installation• PLC Meters (or modules) need to be available to use at installation, increasing the number of meter

variants• There may be particular security issues with data on PLC layer ‘leaking’ beyond the property

Variant 1c: Hybrid Comms Hub to PLC equipped mains powered componentsUnder this variant, a combination of 1a and 1b, both the electricity meter and IHD requires a PLC connection to the Comms Hub. The gas meter connects via RF.

Comms HubRF


IHD

RFRF

WANDCC

PLC

PLC

PLC

Figure Variant 1c

The implications of this variant:• Hybrid Comms Hubs need to be available to use at installation• PLC Meters (or modules) need to be available to use at installation• PLC IHDs need to be available to use at installation• Customer needs to be aware that their IHD connects via PLC and not RF• There may be particular security issues with data on PLC layer ‘leaking’ beyond the property

Variant 2a: Wireless Range Extender to Gas Meter (and other RF devices)Under this variant the gas meter cannot obtain a reliable connection using the standard SMHAN RF hardware. Additional SMHAN RF hardware could be used to bring the gas meter radio within range.

Comms HubRF

Elec Meter

Gas Meter

IHD

RF

WANDCC

RF

RF

Extender / Repeater

RF

Figure Variant 2a

The implications of this variant:• Extender/Repeater equipment to be available and suitable/robust for use – as noted in the

considerations discussion above• The extender/repeater could be used to link to any RF device, as shown below, and could potentially

reduce the number of meter and IHD variants required.

Where the Electricity Meter and Comms Hub are collocated:

Comms HubRF

Elec Meter

Gas Meter

IHD

RF

WANDCC

RF

RF

Extender / Repeater

RF

Figure Variant 2a - alternative

Or where the Comms Hub is located away from smart metering devices, probably to maximize signal strength for the WAN connection (or to avoid significant interference for the WAN):

Comms HubRF

Elec MeterGas Meter

IHD

RF

WANDCC

RF

RF

Extender / Repeater

RF

Figure Variant 2a Alternative 2

Variant 2b: Wired Range Extender to Gas MeterUnder this variant the gas meter cannot obtain a reliable connection using the standard HAN RF hardware. Additional SMHAN hardware could be used to bring the gas meter radio within range using PLC.

Comms HubRF

Elec Meter

Gas Meter

IHD

RF

WANDCC

RF

RF

Extender / Repeater

RFPLC

PLC

Figure Variant 2b

The implications of this variant:• Extender/Repeater equipment to be available and suitable/robust for use• Extender/Repeater with PLC and RF is likely to be more expensive than an RF-only

repeater/extender• Hybrid Comms Hub with PLC hardware is available• There may be particular security issues with data on PLC layer ‘leaking’ beyond the property

An alternative approach to a PLC range extender is to keep the PLC hardware as a stand alone network ‘bridge’ as shown below.

BoxRF PLC

Box

RF

Comms HubRF

Elec Meter

Gas Meter

IHD

RF

WANDCC

RF

RF

PLC

Figure Variant 2b Alternative

The PLC ‘bridge’ could connect to other RF devices within range – this could be the Electricity meter or IHD as shown for 2a above.

Variant 2c: Gas Meter Extra RadioUnder this variant the gas meter cannot obtain a reliable connection using the standard HAN RF hardware. It is either not possible or practical to use a repeater or extender to connect the gas meter.

The variant makes use of a different radio – typically at a different frequency, to establish a connection. It is known that 433MHz or 169MHz radios could achieve connections, albeit with potential compromises on data rates, that would not be possible with the anticipated 868MHz or 2.4GHz radios being considered for the SMHAN.

An example of the type of radio module is discussed here: http://lnkd.in/HG285b - a 169MHz radio supporting Wireless M-Bus and complying with prEN 13757-4:2011

The power, design and battery implications of a second radio for a gas meter would be critical considerations.

http://lnkd.in/HG285b

Comms HubRF

Elec Meter

Gas Meter

IHD

RF2

RF

WANDCC

RF

RF2

RF

Figure Variant 2c

The implications of this variant:• Comms Hub would need to be capable of accommodating an additional radio• Suitably equipped gas meters (or external modules) need to be available, adding to the number of

meter variants• ‘Standard’ SMHAN Radio in gas meters may be redundant

An approach that could be considered would be for the RF2 link to be achieved outside of the Meter and/or Comms Hub, as shown below. This would result in no requirement for a HAN variant gas meter, but may reduce the robustness of the RF2 link, even if this is battery operated and sealed. In the illustration, the ‘Box’ devices are acting as a bridge for the HAN RF network.

Comms HubRF

Elec Meter

Gas Meter

IHD

RF

WANDCC

RF

BoxRF2RF

BoxRF2 RF

RF

Figure Variant 2c Alternative

Variant 3: Gas Meter with No HANUnder this variant the gas meter cannot obtain a reliable connection using the standard HAN RF hardware, and the use of other variants is not appropriate. The gas meter still needs a WAN connection, so has its’ own WAN hardware, or ‘Comms Hub Lite’. There is no ‘in home’ provision of gas consumption information to the IHD.

Comms HubRF

Elec Meter

Gas Meter

IHD

RF

WANDCC

RF

RFWAN

Figure Variant 3

The implications of this variant:• Suitably equipped gas meters (or external modules) and commercial arrangements with DCC need to

be available• Gas consumption can be made available on IHD, but this is likely to be via the WAN connection to

the DCC, and then to the IHD via Comms Hub where it would be stored/mirrored• There are particular security provisions relating to the Comms Hub – a gas meter fulfilling a

connection to the DCC independently of a Comms Hub would need to meet all of those requirements• HAN Radio in gas meters may be redundant if these are universal and standard

15.2.3 Summary Of Implied VariantsThe table shows the maximum possible number of variants for each type of device, and in one sense, shows a ‘worst case’ position

Type of Device Standard HAN Hardware Variants

Comms Hub RF RF+PLC, RF+RF2

Electricity Meter RF PLC, RF+PLC

Gas Meter RF RF+RF2, WAN

In Home Display RF PLC, RF+PLC

Extender RF RF+PLC

For the 5 ‘types’ of device considered in this paper – there are 14 variants from a basic assessment, with more potentially being required to support dedicated wires and other challenging installations. This may not be an exhaustive list of potential variants.

HAN WG Recommendation(s):At the time of preparing this report, a number of key issues remain outstanding;

- Range of architectures and options, and a principle for variants- Prevalence of premises where these ‘variant’ approaches may be required, particularly for multi-

occupant buildings, remains an estimate – and within that estimate, the variations (and therefore possible HAN variants) are not known

- Practical suitability, and commercial availability, of tested and proven Wired HAN options to provide a reliable alternative

16 The HAN WG cannot make clear recommendations on HAN variants beyond the need for further design consideration of how to physically achieve the requirement for total SMHAN connectivity with no compromise to robustness.

17 Particular testing on use of different approaches – wired, mesh, 2nd wireless – and the operational and commercial issues arising from these should be considered for multi occupant buildings.

17.1 HAN ModularityThis section includes a summary of the HAN Working Group’s position and recommendations on SMHAN modularity.

There are several approaches to providing modularity for the SMHAN, two examples being:

(a) Full modularity applied to every SMHAN communications transceiverThis implies that every SMHAN-connected device would include internally a standardized physical interface into which is plugged a field-replaceable module. This means that the SMHAN technology can be selected for each installation by selecting the relevant modules. It also allows new technologies may be added to existing installations, or existing technologies substituted, without having to replace every Smart Metering System device.

(b) SMHAN modularity applied to the Comms HubThis would involve a similar internal standardised physical interface to option (a) above, but only in the Comms Hub. It would allow the same Comms Hub to support different SMHAN technologies. If more than one interface was provided it would enable multiple technologies to be used simultaneously on the same SMHAN. It would also mean that future changes to SMHAN technology could be implemented without having to change the entire Comms Hub.

There is no formal Design Requirement that calls for modularity in the SMHAN. Nevertheless, there has been much discussion of SMHAN modularity, especially within the HAN and Architecture Working Groups and the wider Community of Technical Experts.

Stimulating this discussion is a widespread recognition that the pace of technology change in communications systems is fast, in comparison to the 15 year design lifetime of SMHAN metering devices. It can be expected that new and improved wireless , wired standards and technologies will emerge during the lifetime of the Smart Metering System. There is also some uncertainty about the long-term situation regarding congestion and interference in some frequency bands which are otherwise attractive for operating the SMHAN. This raises an important question:

Should suppliers and equipment vendors invest more now in development and equipment costs to build-in SMHAN modularity, in order to guard against potentially expensive SMHAN technology change earlier than anticipated?

At present, through the use of assumptions and cost estimates, it would be possible to build convincing economic cases supporting or opposing SMHAN modularity, particularly in the Comms Hub. A case could be assembled that shows the cost of replacing more than a certain percentage of Comms Hubs within a certain time to be more than the cost of modularity which avoids (or reduces the cost of) such replacement. However, nobody can say for sure whether this percentage of Comms Hubs will need to be replaced, so the case cannot be validated at this time.

A key barrier to any form of SMHAN modularity is the requirement to define and agree a standard interface for the modules before design, manufacture and deployment can proceed. Whilst some candidates have been suggested (e.g. CCL’s UMI and USB) each would take time and money to develop, and to incorporate

into product designs and would require co-ordinated commitment by all energy suppliers and equipment vendors. Industry has, so far, not been convinced that the benefits of modularity would outweigh the time, effort and cost of seeking agreement and making it happen.


18 As a consequence of the above, the HAN Working Group recommends that modularity is not mandated in the SMHAN elements of Smart Metering System Devices.

The following points are relevant to this recommendation:

The cost of Comms Hubs will be kept as low as possible in order to minimize the cost of replacement, should a change in SMHAN technology be required in some or all premises in the future.

Provision for different SMHAN standards at launch will be achieved by specifying a set of Comms Hubs which support the desired combination of standards.

Comms Hub vendors may choose to achieve competitive product pricing by including modularity within their products. Any design features required to achieve such prices (e.g. connectors or selectively populated PCBs) remain within the control of each vendor and thus do not incur the cost and time required for cross-programme standardisation.

Updated Comms Hubs may be developed later to include new SMHAN technologies or standards that meet the SMHAN system requirements.

However, it should be noted that, in the absence of modularity, post-installation SMHAN issues (such as changes to local radio or wired propagation or interference conditions) may require entire Smart Metering Systems in some premises to be replaced before the end of their expected lifetime with an alternative communications solution, in order to restore reliable SMHAN operation.

The above recommendation is based on currently available information. However, it may be re-visited by industry at any time during the life of the Smart Metering System. It may be that industry will wish to review its position in the future in the light of new information, for example:

If responses from SMHAN vendors to questions on long-term robustness of their solutions (e.g. in the presence of increasing interference) suggest that even the best candidate technology available today may within a few years degrade in performance in a significant proportion of premises, to the point where replacement is necessary.

If operational experience with early SMHAN installations leads to an unacceptable number of problems, where rectification costs would be significantly reduced by the ability to replace SMHAN communications modules in some or all devices, rather than the entire devices.

18.1 Connection of Other Customer DevicesAs mentioned in section Error: Reference source not found above, provision is made for connection of other customer devices (e.g. Home Automation Systems) via an Approved Gateway SMHAN Device, as required in HA.13. Such Devices may be produced by a variety of vendors and made available to customers via retail channels. Provided they are Approved, and then Authenticated for connection to the customer’s SMHAN, then they can gain access to allowed data on the SMHAN and instruct other SMHAN Devices to carry out allowed actions.

A local consumer interface with the SMHAN (that connects the meters, comms hub and mandated IHD) is required for;

- Data access (although this can also be achieved over the WAN)- Home energy management systems (e.g. a ‘Consumer HAN’ or ‘CHAN’)- Smart appliances

There are a number of options to achieve this;- Option A: A wireless Gateway between the SMHAN and Consumer HAN

Could be implemented by including a radio transceiver operating to the SMHAN standard (or standards) in a device (e.g. an In-home Display), together with the appropriate firewall to protect SMHAN security. This device would also include a Bridge to another wired or wireless standard used by Home Automation Devices which the customer wishes to connect. This option implies that Approved SMHAN Devices will need to be available for customers to buy. These will need to be Type Approved, as for any SMHAN device. A number of Gateway SMHAN devices could be connected to a single SMHAN.

- Option B: A physical port on the comms hub for the consumer to plug in a Consumer HAN dongleCould be implemented by providing a customer-accessible physical port on the Comms Hub, to which additional communications devices can be connected. In this case, the Firewall would be included within the Comms Hub, increasing the security of the SMHAN. Note that such an approach might not be applicable to outside locations due to the requirement for environmental protection of the port. A decision on a common physical port standard and communications protocol would need to be made. This port would also increase the cost of the Comms Hub, but devices connected to it would not need to be Type Approved, as they are outside the SMHAN.

- Option C: Build Consumer HAN connectivity (e.g. Wi-Fi) into the Comms HubTechnically similar to option A, but utilising a more appropriate transceiver within the Comms Hub.

WAN

SMHANPort 1

GasElec

MandatoryIHD DCC

TrustedThird Party

AuthenticationCentre

Firewall

Firewall

Suppliers

WAN

ConsumerHAN

Devices

Plug-inConsumer HAN

Gateway

Wirelessbridge

‘Open’Consumer

Physical Port

MainSMHAN Port 1

Comms HubElectronics

Comms HubEnclosure

PowerSupply

MainsInput

Comms Hub

‘Closed’SMHAN & WAN Ports

(USB optional)

SMHAN

ConsumerHAN(s)

A

B

A B C Consumer HAN options

WiFi

C WiFi

ConsumerHAN(s)

Figure Customer HAN Connection Options

Option A appears to minimise design complications, so long as the security measures which are built-in to the devices and the profile for an IHD are deemed adequate. Discussions within the group indicated that there was a clear requirement for access control rules for the operation of such devices for Energy Services Companies.

Gateway device functionality and hardware will not be required for all customers – some may choose never to add their devices to a consumer HAN (CHAN), or for their CHAN to connect to the SMHAN. For some, the purchase of a device with multiple transceivers (wireless and wired or multiple wireless), such as an appropriate internet router, would allow them to access the information and services on an SMHAN once the Gateway Device has been authenticated to join the SMHAN.


19 The HAN WG did not express a collective preference for any option on Gateways, but have used (a) as a working assumption.

19.1 HAN Spectrum OptionsThe HAN WG has inherited the assumption that radio will be the default technology for Smart Metering Home Area Networks (SMHANs). Radio solutions are quick to install and offer great flexibility for future

expansion. However, in-building radio networks can be challenging to design and deploy, especially if they need to work within many different types of building (as is the case with the GB housing stock) and for many years (ideally 15 years or more for the SMHAN).

Wired alternatives will be available for SMHANs where radio propagation is difficult, for example due to existing meter positions, buildings with high attenuation or interference from other networks. However, wired networks can be expensive to install and upgrade, and are not without their own technical issues.

The HAN Working Group has identified a long list of candidate SMHAN wired and wireless technologies. It has designed an evaluation process to support the selection of one or more of these for use in UK SMHANs.

As part of the work of the HAN WG, with the support of the Technology Strategy Board and the Smart Energy Special Interest Group, Astutim were asked to take an independent look at radio-related issues that may impact the suitability of technologies for the UK SMHAN requirement. A brief initial study was carried out, focusing on spectrum availability, potential interference and robustness, the results of which are summarised below.

19.1.1 SMHAN Radio Spectrum Study ResultsThe HAN WG Radio Spectrum Study surveyed existing and potential new frequency bands which could be used for a GB SMHAN. It looked at both licensed and license-exempt spectrum, and included a dialogue with Ofcom about future planning of both types of spectrum. The study looked at the suitability of each band to meet the technical requirements of the GB’s SMHANs. This included available bandwidth, and suitability for supporting a modern spread-spectrum or frequency-hopping radio system. It also looked at the susceptibility of each band to interference from other devices, both now and in the future.

The study concluded that there are four strong candidate frequency bands, each of which has the potential to meet the minimum requirements. These bands, and their assessed position regarding co-channel and adjacent channel interference, are summarised in the table below.

Number

Band Potential for Co-channel interference

Potential for Adjacent channel interference

1 Current 868 MHz band Low Increasing due to new 800 MHz band

2 Possible new 870-876 and 915-921 MHz bands

Very low Medium – effect of new 800 MHz band allocations needs to be assessed

3 DECT (1880 -1900 MHz) Low Static – DECT devices should be resilient to this

4 2.4 GHz ISM High and increasing Not a significant issue compared with co-channel (in-band) interference

The 2.4 GHz ISM band (Number 4) is seen as one obvious choice for the SMHAN. However, its continuing popularity for other applications, including Wi-Fi networks used increasingly for streaming video, mean that even the techniques used by leading HAN technology providers to maintain performance in the face of interference may be insufficient to guarantee operation in some locations within the projected 15 year lifetime of the system (detailed ‘co-existence’ testing in representative SMHAN environments is required to confirm or deny any issues here). The possible new bands (870-876 and 915-921 MHz, Number 2) and DECT (1880-1900 MHz, Number 3) are potentially attractive, but each would require time and investment by industry before they could be used in a mass-deployment system, such as the UK SMHAN. This initial study did not uncover evidence that would suggest a preference between Numbers 2 and 3.

In addition to the above four alternatives, it is possible that the programme could seek to acquire rights to use spectrum that is owned by commercial organizations. This possibility has not been studied in detail within the initial study.

In order to be considered as a candidate, any proposed SMHAN solution needs to demonstrate a proven ability to meet the specified operational requirements in the presence of representative worst case interference conditions. It is recommended that promoters of the candidate solutions should be invited to submit evidence that their systems will operate reliably over the lifetime of the system. Promoters should also be asked to define a series of tests that will demonstrate compliance of their solution in terms of data throughput, error rate and latency in the presence of levels of interference that can be expected in their chosen band within the 15 year system lifetime.

19.1.2 The Way ForwardAny decision on GB SMHAN radio technology will need to balance the risk of long-term reliability issues (and potential costs) with the need to meet the system rollout timescale of smart meters installed in all GB homes by the end of 2020. There may not be a system in production now which can meet both these requirements. The figure below illustrates three alternative options which the Programme, or industry, could adopt:

Option 1At least one existing technology presents convincing evidence that it will be robust long-term.

Option 2Evidence suggests that an existing technology will be satisfactory in the medium term, but may be problematic long-term.Programme evaluates alternative new technologies and selects one for introduction later. Existing technology remains operational where installed.

Option 3Programme decides to promote and fast-track a new technology now.Long-term solution from the beginning but may delay start of rollout. Time

Figure SMHAN Radio System Options

Option 1 may be chosen if at least one solution emerges that meets all the agreed evaluation criteria and is able to provide convincing evidence that it will be robust over the long-term for the great majority of installations in the real-world GB SMHAN environment.

It is possible that the evidence presented fails to make a convincing case that any existing solution will be sufficiently robust in the long-term. However, the evidence may be strong enough to make a case for at least one existing solution working adequately in a proportion of premises, which can therefore be prioritised for early installation. In this instance Option 2 can be chosen. This would enable rollout to begin on schedule, whilst allowing time for manufacturers to deliver an improved solution that will be robust in the long term in the great majority of GB homes.

If the evidence presented for existing solutions is weak and the Programme believes the risk of performance problems in the medium term is high (even when early-install premises are selected with care) then it may be that Option 3 is the only viable solution. The time taken to bring an alternative system to production may result in some delay to the start of rollout, but this could be balanced by the reduction in risk of SMHAN components failing in the field and needing to be replaced before end of life.


20 The HAN WG notes the concerns regarding operating frequency, long term reliability and cost, but agreed that the main issue facing the Programme is having a commercially available and proven solution to deliver economic connectivity to the majority of premises. Therefore operating frequency, long term reliability and cost need to be considered alongside other considerations on the suitability of an SMHAN.

20.1 HAN Technology ChangeIn selecting SMHAN solutions for use in GB smart metering it is intended that these solutions will continue to work and be suitable for 15 years or more. It should be understood however that there is always a risk that there will be a wish or need to change one or more technologies used in the SMHAN.

20.1.1 Reasons for changeThere are 2 main reasons for considering a change of technology in the SMHAN;- Problems with original choice of SMHAN solution- Compelling new technology becomes available in the marketThese are explained in more detail below. The principles of the Radio System change figure in section 12.4.2 also apply to overall SMHAN solution options.

20.1.1.1 Problems with original choice of SMHAN solutionThere are three main types of issues that could arise; commercial, technical and regulatory;

Commercial: e.g. SMHAN solution X was available from 3 vendors and all 3 vendors go out of business within 10 years, making it difficult or impossible to continue to deploy new devices and support existing devices in the field.Technical: e.g. SMHAN solution Y no longer works well because other home products and services using the same physical medium increase in usage so much that it renders that physical medium completely congested and unavailable for SMHAN use.Regulatory: e.g. New UK or EU regulations come in to either limit the usage of SMHAN solution Z or allow new products and services that could limit the usefulness of that solution.

Note that all of these scenarios all attract some level of risk, and it is particularly difficult to judge the likelihood of these risks materialising.

20.1.1.2 Compelling new technology becomes available in the marketThere are a number of use cases and possibilities here;

(a) In the future some new radio or powerline technology may become available that fundamentally changes the market either in terms of cost, propagation, bandwidth, power consumption or all of these attributes.

(b) It may not be that existing deployments are deemed unsuitable, but the step change in functionality may have a profound impact on the success of the smart metering programme either in terms of financial return or consumer experience and behaviour, such that it is decided that all future deployments should move to this new technology.

Perhaps GB smart metering deployments start in 2014 with SMHAN solution A, even though it is recognised as less than perfect, however in parallel a programme is instigated to develop a new SMHAN solution and standard, which will not be available and mature until 2016. Thus there would need to be a plan to upgrade to the new SMHAN solution some time in the future.

20.1.2 Types of Technology Change

20.1.2.1 Physical Technological ChangeSome technology changes require a physical change to products deployed in the field, e.g. swap out one type of electric meter using SMHAN solution C for another meter that uses SMHAN solution D.

For example, if SMHAN devices are shipped with 2.4GHz radios supporting one SMHAN solution and it is decided to introduce a new SMHAN solution that uses 1.9GHz radios, the existing 2.4GHz radios will almost certainly not be able to support the new radio frequency, so they will have to be swapped out.

20.1.2.2 Changes to Technology involving software onlySome changes to the SMHAN solution may involve only an upgrade to firmware or software on existing deployed devices. Such changes may still be fairly fundamental in nature and may have a large impact on the SMHAN performance in different ways, but they do not necessarily require replacement of existing hardware or products in the field.

For example, if there is some installed base of ZigBee Smart Energy 1.1 SMHAN solutions, some software-only technology change use cases come to mind, e.g.;

- IP: There may in the future be a compelling reason to adopt Internet Protocols throughout the smart metering system, including the SMHAN, and it may therefore be useful to upgrade to ZigBee Smart Energy 2.0, which is IP-based, and which should run on deployed hardware, requiring only a software upgrade.

- Coexistence : e.g. if the 2.4GHz frequency becomes more congested and more difficult to work with, one solution may be to implement a frequency hopping regime in software to spread the communications across all available channels and improve robustness. Such a solution could be implemented in software and existing deployed devices could be upgraded in the field.

20.1.3 Development of a new SMHAN Solution / Standard

One option that has been discussed is to choose a physical medium (probably a radio frequency) and develop a new SMHAN solution specifically for use in GB smart metering deployments. There are pros and cons to such an approach.

ProsThis new solution could be purpose designed for GB smart meteringThe option of licensed bands could be looked at, eliminating any potential interference or coexistence issuesIt may be able to eliminate functional or performance gaps in existing solutions

Cons It takes some time to develop a new solution, especially if it has to be an open standard, requiring consensus from stakeholders, and it requires considerable investment in time/resources from those stakeholders.

Existing solutions and standards, especially those that have been deployed in other markets, will have developed a level of robustness and maturity that will need to be replicated in any new solution. This takes time, effort and pilot deployments.If the solution requires new silicon and is very specifically targeted to GB, will the market size be such that it will be attractive to multiple silicon vendors to design and supply silicon for the market at a cost competitive price?Even if the new solution is to take an existing application or networking protocol/standard and apply it to an existing physical medium, this also takes a lot of time and effort from stakeholders and silicon/stack vendors. Bearing in mind that those with expertise in the application/networking protocol may not have any commercial interest in making it work with a different physical medium (which they may not have products for).Who will invest time and money in this effort?

Anecdotal timescales for standards development;ZigBee Alliance

• ZigBee Smart Energy 1.0 Application Profile (starting with an existing proven physical medium and an existing proven networking solution, adding a new application profile): started with an initial meeting in December 2006 and was completed with spec complete and products certified in May 2008 – 18 months (product releases took another 3-6 months).

• ZigBee 2007 (Pro) networking spec (starting with an existing proven physical medium and adding functionality to an existing networking standard): Initial rough technical requirements document in Summer 2006, completed (spec) and certified platforms in October 2007 (~16 months), with products release in December 2007 (~18 months).

• ZigBee Smart Energy 2.0 Application Profile and IP Stack (starting with an existing proven physical medium, taking some existing networking and application protocols and modifying them, adding some new protocols): Work started in January 2009. As of June 2011, work is ongoing and planned to complete with certified products at the end of Q3 2012 (3.5 years +).

Some new standards (e.g. new radio frequencies/standards) may require the development of new radios or plc transceivers, and even if a small number of initial implementations exist, it would be preferable for other silicon vendors in the market to develop their own products to compete in the market and ensure cost effectiveness of solutions and innovation. Development of an entirely new silicon product can take 2-3 years and £3m - £7m in development costs, an investment that would need to be covered by future sales of silicon. For example, assuming a minimum of 3 vendors for RF or PLC chips for GB SMHAN devices, some of those vendors would need to invest 2-3 years and £3m-£7m developing solutions for less than 30 million unit sales over 5-8 years.

HAN WG Recommendation(s):21 The HAN WG recommends that the content in this section is noted by the Programme and Industry

when considering the next steps for smart metering. It will be difficult, but not impossible, to change HAN technology decisions once they have been established.

21.1 Post Installation/Environmental ConsiderationsThe HAN WG, in discussion with the Difficult Meter Positions Working Group, have considered what provisions might be made where there are changes in the environment for the operation of the SMHAN.

Examples offered of changes that could affect the efficient operation of an installed SMHAN include building works, renovation, positioning of domestic items (furniture, white goods etc.). Specifically, putting a large stainless steel fridge freezer next to the IHD could make it ‘invisible’ to the SMHAN.

The types of challenges and post-installation issues should only be the same as those that might affect the SMHAN prior to installation, as have been documented by the Difficult Meter Positions WG. The methods used to address these issues will also largely be similar – use of an alternative physical carrier, an extender or other method of providing reliable connectivity.

The potential incidence rate of post-installation SMHAN connection issues is not known, and will be driven as much by the selection/specification of SMHAN hardware as it will be by customer activity.

The group concluded that there may be an issue with the diagnosis of SMHAN connection problems after an installation. Data items to provide diagnostic information on signal quality have been recommended by the HAN WG. Monitoring these items, locally or remotely, would enable a Supplier to determine if the IHD, or Gas Meter, were experiencing difficulties in maintaining a reliable SMHAN connection. In particular, the ability for a Supplier to recognise a problem before it leads to a failure could reduce significantly the cost of repair. Engaging the customer on the telephone, with the conversation supported by diagnostic information, could allow some problems to be resolved without the need for a visit.


22 That Suppliers develop (collectively or individually) processes to diagnose SMHAN connection issues after installation using the data items recommended by the group

23 That Suppliers use appropriate techniques to restore reliable SMHAN connection where post-installation problems occur

23.1 Wired TechnologiesThe existing HAN Evaluation Criteria and anticipated Link Budget tests from the Difficult Meter Positions WG largely focus on wireless HAN technologies. We expect PowerLine and wired HAN technologies to provide contingency where use of radios is not practical or possible.

Note that other, dedicated, wired technologies are not covered by this document.

23.1.1 Classification of Powerline technologiesPowerLine technologies use the electrical network to transmit information. They are generally referred to as PLC technologies (Power Line Carrier). The principle of PLC technologies consists in superimposing a high frequency and low amplitude modulated signal on the 50Hz electrical signal. This additional high frequency signal contains the information to be transmitted over the electrical network.

Figure - Principle of PLC technologies

It is possible to classify PLC technologies by the frequency band they are using for the carrier signal, as well as on the type of modulation that is used.

23.1.2 Frequency spectrum: narrowband or broadband PLCBased on frequency band criteria, there are two families of PLC technologies:

• Broadband PLC uses spectrum from 500 kHz to 30 MHz (typically 1.6, or 2, to 30 MHz) or above and is delivering high data rates (data-rate of tens of Mbps, announced up to 200 Mbps).

• Narrowband PLC uses the band from 0 to 500 kHz, and is characterised by lower data rates (data rates will be detailed later as they depend on the modulation type).

Some broadband suppliers are starting to look at frequencies above the 30MHz level, these are aimed at ultra wide bandwidth applications (such as media streaming) and will not be considered by this paper.In the narrowband spectrum, it is possible to differentiate technologies working on very low frequencies, under 9 kHz, known as ripple control. Designed for one-way (sometimes two-way) very low data-rate communications over the grid, they are widely used to send messages from a substation to remote downstream appliances (e.g. meters or street lights). Examples of technologies are TFCM over the French grid, and Twacs offered by the company ACLARA (bidirectional). Their very low frequency enables very good and reliable propagation range. However, being used for very simple communications and having a very low data-rate, they are excluded from the scope of our HAN Wired options.

In Europe, the only standard in force for narrowband PLC is the EN50065-1. This standard proposes a subdivision of the narrowband spectrum into 4 frequency bands. It also defines for each band maximum levels of emission and the maximum perturbation levels (conducted and radiated) in link with CISPR22 (EN50022). These bands are:

• Cenelec A : 3-95kHz• Cenelec B : 95-125 kHz• Cenelec C : 125-140 kHz• Cenelec D : 140-148.5 kHz• The 150-500 kHz band is not usable because of AM broadcasting.

While the CENELEC B, C and D bands can be used for any types of applications, the CENELEC A band is dedicated to utilities applications. The latest version of EN50065-1 standard states:

Band 3 kHz up to 95 kHz

Frequencies in this band shall only be used for applications for monitoring or controlling the low-voltage distribution network, including energy usage of connected equipment and premises.

NOTE A typical example of an application in this band would be metering communications.

Examples of technologies working on the Cenelec A band include: PLC technologies used by ERDF in France for metering (S-FSK and G3 experimentations), Meters & More technology of Enel in Italy, Lonworks used for building automation, Prime driven by Iberdrola in Spain. Note that PLC G3 could as well be used on other frequency bands: other Cenelec bands in Europe, FCC in the USA, and ARIB (up to 500 kHz) in Japan. Most of these technologies have initially targeted grid applications; however, they could very well be appropriate for in-home applications.

An important majority of broadband PLC technologies are operating in the 1.6 to 30 MHz band (for example BT Vision products installed in GB homes, the forthcoming rollout of the YouView streamed TV service is expected to vastly increase the number of PowerLine deployments. It is expected that forthcoming products will use 2-50 MHz or even 2-100 MHz frequency bands. The frequencies from 500 kHz to 1.6 MHz are not used in practice currently.

On the broadband spectrum, there is no standard in force for the maximum transmitter output levels. The main technologies on the market for broadband PLC are: Home Plug AV, HD-PLC of Panasonic (Japan), and former DS2 recently bought by Marvell.

The main technologies for narrowband and broadband are summarised in Figure .

Figure – Narrowband and Broadband techniques

23.1.3 PLC Modulation techniquesAnother important characteristic of a PLC solution is its modulation technology. It is possible to distinguish 3 generations of modulations that apply mainly to narrowband PLC technologies. These are summarized below and shown in Figure 3. The third of these also applies to broadband technologies.

These modulations are:• 1st generation: based on mono carrier modulation. This is the oldest and simplest modulation to

use. It uses a single frequency and is thus very susceptible to perturbations that may affect that particular frequency. It is widely used by narrowband products developed by utilities or for energy services products. The modulation can be done on the amplitude, the frequency or the phase.

o Amplitude modulation is not much used (amplitude information is not easy to decode in harsh power line environments, mainly because of the varying attenuation).

o Frequency modulation is used by ENEL in Italy with the Meters & More solution (FSK modulation) and EDF in France with the PLAN Protocol (S-FSK modulation).

o Phase modulation is used by Lonworks (B-PSK modulation).Typical data rates for these technologies are 1200 to 4800 bit/s.

• 2nd generation: based on spread spectrum modulation (like DSSS, FHSS, etc.). 2nd generation technologies provide more robustness than 1st generation whereas no real improvements can be noticed on typical data rates. There are none, or very few, products or projects currently using second generation PLC over narrowband spectrum, despite an important development project by Endesa some years ago.

• 3rd generation: based on multi carriers modulation (OFDM - orthogonal frequency division multiplexing). Outside of the PLC world, this technology is used for ADSL, Digital TV, Wi-Fi; Wimax, etc. The principle of OFDM consists in sending the information over a large number of frequency carriers within the available spectrum, thus providing a high robustness to impulsive noise.

o As mentioned before, OFDM modulation is used today for most of the broadband PLC products. This form of modulation is also used for Wi-Fi, Wimax, Digital TV, etc.

o For narrowband PLC, ODFM solutions are in development. Once complete, these systems should reach higher data rates and deliver more robustness thanks to a better use of the frequency band than for 1st and 2nd generation PLC technologies. The two main narrowband solutions using OFDM are Prime and G3.

Expected data rates for narrowband OFDM products:• PRIME announced up to 128 kbps ,• G3 announced up to 35kbps on Cenelec A band and up to 200kbps on full FCC band.• up to 35kbps for G3 announced – G3 announced up to 35 kbps on CENELEC A band and up

to 200 kbps on full FCC band)

Figure – Classification of modulation technologies for narrowband PLC

Broadband technologies typically use various types of OFDM modulation scheme. Figure 4 below shows how these sit with respect to the first and second generation schemes which are typically used for narrowband systems.

complexity

robustness

2nd generation

3rd generation

1st generation

Modulation technologies

Figure - Modulation types & generations

Here are 2 examples of PLC profiles, the ENEL Meters & More and the G3 PLC.

Figure - Meters & More PLC Profile

23.1.4

Figure - G3 PLC Profile

23.1.5 Constraints of PLC solutionsThe main issues that a HAN transmission signal can face are the following:

1. Attenuation of the signal due to the environmental conditions2. Noise (permanent or impulsive)3. Interference with other signals

23.1.6 Signal attenuation

When studying wireless solutions, the attenuation is caused by:o the distance between transmitter and receiver

o all the obstacles such as walls, doors, etc. that can be characterised by their thickness and composition

When studying wired PLC solutions, the attenuation is cause by:o the length of the electric cabling between transmitter and receiver (note: in UK housing the

actual distance a signal travels may be several times the physical distance between two PowerLine units due to the ring main architecture employed for circuitry)

o the number (or density) of derivationso the connected load (direct impact on the network’s impedance)o a change of cable type (underground to aerial, section, type of neutral cable, etc. – applies to

grid, not in-home)o transformers (G3 PLC developed by ERDF is able to pass low-voltage / medium voltage

transformers – which in average have an attenuation of 60dB on Cenelec A – applies to grid, not in-home)

o the number of ring mains the signal traverses. i.e. the number of consumer units the signal passes through between PowerLine endpoints

These parameters were primarily identified by EDF when working over the grid, and most are also applicable to a home environment, though it should be noted that the attenuation figures will differ for home systems.

23.1.7 Home Wiring TopologyThere is no guarantee that two sockets which are physically close together will actually be on the same ring main or connected by only centimetres of cable; however, in the majority of UK housing stock, this will be the case if the sockets are in the same room. It is unusual (though not rare) to find sockets in the same room to be on different rings or to be wired via an unexpected route. [It may be worth noting that this problem is, however, very usual in office buildings and other commercial/industrial premises, though this falls outside the current scope.] While it may be possible to make a sensible guess about the topology of the wiring within a room, estimates about the run length of the unseen cabling are very difficult to make.

Wherever the Powerline signal needs to cross a consumer unit there is an associated signal loss; this is further compounded in properties with extensions where multiple consumer units have been installed. Additionally poor quality wiring and/or sockets as well as ageing wiring can also lead to signal degradation.

23.1.8 NoiseAs for Wireless solutions, PLC can be affected by noise on the mains wiring , typically introduced by connected appliances.

Noise can affect all, or a part, of the PLC signal; the amount over time depending on the type and number of appliances that are active. Noise can be:

• Continuous (motors such as are found in fridges, washing machines, hand held tools etc., generate a continuous noise whenever they are operating)

• Impulsive (mobile phone chargers with switch mode power supplies, automatic or manual switching on and off appliances, heaters, etc. generate ‘spikes’ or impulses of noise when they are switched on or off)

Characteristics of noise in GB homes are not known, and while some papers try to model noise with statistical approaches, there is no real consensus within the PLC community. It is extremely difficult to model what the noise level in a ‘typical’ home looks like as it is entirely dependent on the electrical devices which are active at any given time. Not only will no two homes look the same, but one home may look different from one day (or even minute) to the next.

To cope with noise, the solution at the physical level is to choose an efficient modulation scheme, by implementing strategies to measure the link quality (channel estimation techniques) to enable modulation scheme adaptation and signal emission adjustment and change the signal emission frequency (within regulatory limits).

Well documented interferers of Broadband PowerLine devices include switched mode power supplies (such as are used in mobile phone chargers), transformers for lighting units, low power CFL bulbs, dimmer switches for lighting, surge protectors and handheld motor-based devices such as kitchen equipment and hair dryers. Some of these interferers are inevitably more transient than others. Unlike, for example, streaming video, the SMHAN operates at a relatively low data rate and messages can be re-transmitted if a first attempt fails. So, a PLC system suitable for the SMHAN will be more tolerant of impulsive than continuous noise, where it can simply try again if a message is affected by an impulse of noise at the first attempt.

23.1.9 Interference

Interference with other signals is also an issue for PLC solutions. There is potential for interference when two different technologies share the same frequency band and do not have coexistence strategies.

• On the broadband spectrum, there is no restriction on the use of the frequency, and there are already large numbers of products which utilise these frequencies in use in GB homes. Most of them are not only incompatible, but actively interfere with one another as they are seen only as unintelligible noise by the competing PowerLine units. However, products based on standards from the ITU (G.hn) and IEEE (P1901) standards bodies will become commercially available as of 2012 and these have co-existence capabilities built into them. Crucially, they will co-exist only with solutions based on another of the new standards. However, current solutions will continue to be in use in GB homes for a long time. Legacy devices would be a major problem if the smart metering system were to use a broadband PLC solution for the HAN.

• Another notable user of the broadband spectrum is the amateur radio community (“Hams”). In existing UK roll-outs of Broadband PowerLine there have been a limited number of instances where PowerLine installs have interfered with Ham Radio. These instances have been small in number (accounting for far fewer than 0.01% of deployments). The providers who deployed the PowerLine have addressed the situation either by supplying new Powerline adapters which avoid the relevant frequency (a process known as “notching”) or – in extreme cases only – replacing the PowerLine network with an ISP-installed secondary home network solution.

• More recently, ADSL2+ has been rolled-out as a new generation of broadband connection. This utilises frequencies between 1.1MHz and 2.2MHz, which overlaps with the range used by Broadband PowerLine (which starts at 1.6 or 2MHz) and some small instances of radiated interference have been noted by telecommunications operators which has led to degradation of the consumers’ broadband speeds. This has been limited to date due to the relatively small footprint of both Broadband PowerLine and ADSL2+ enabled exchanges. Should Powerline be used more widely, in conjunction with a completed roll-out of ADSL2+, the number of interference issues can be expected to increase significantly. There may also be an issue with BT’s proposed rollout of “fibre-to-the-cabinet” (FTTC) services, which rely on VDSL for the link into customer premises.

• On the narrowband spectrum, as seen earlier, the CENELEC A band guaranties a use for utilities in Europe. This prevents any home product from using these frequencies – and if products not provided by utilities do so, they are not respecting the regulation in force. Other bands B, C and D, could be used as well, however, the frequencies are usable by any other device.

Examples of products working on these bands are KNX and Echelon LONWORKS solutions, on the Cenelec C band. However CENELEC C defines a coexistence mechanism – CSMA/CA access mechanism and the use of a 132.5 kHz carrier during transmission is mandatory.

In addition to the ADSL2+ overlap highlighted above, narrowband Powerline standards over the CENELEC bands cross part of both of the ADSL (25.8KHz-1.1MHz) and the ADSL2+ bands .

Footprint of Broadband products in GB:There are no definitive estimates of the footprint of Broadband PowerLine usage in GB homes. Information is difficult to obtain from the various participants: the telecommunications operators are sparing with their information, and the retail vendors are known to exaggerate their footprints as it serves their commercial purpose. It seems reasonable to assume that the two main technologies in the UK have each shipped to 500k-1M homes. How many are actually in use is not known. Where they are in use, it would be safe to assume that these two technology groups do not overlap.

23.1.10 Overcoming environmental constraints

23.1.10.1 Recommendations for a solution

To overcome the obstacles listed above, recommendations would be:• Generally, to work on lower frequencies to increase range: narrowband PLC should reach longer

distances than broadband, providing that the lower data rate meets the requirements.• Avoid frequency bands where existing sources of interference are present. This would exclude the

use of a broadband PLC solution where a customer already has broadband PLC products (BT vision for example). There, only narrowband solutions remain, and it is important to check that data rates they offer can meet GB SMHAN requirements.

• Choose an efficient modulation: PLC using an OFDM modulation has reasonable data rates and is better designed to overcome noise or perturbations, having the ability to adapt its utilisation of the frequency spectrum.

• It is important to consider multi-hop topologies (i.e. topologies where home devices would not be in direct sight of the PLC coordinator). This should not be a big issue since PLC technologies usually include repetition or routing mechanisms.

23.1.10.2 Understanding GB homes constraints

To evaluate PLC technologies for the SMHAN and validate a choice, there is a need to understand which levels of constraint apply to GB homes. This could be achieved through on-site measurements (as it is currently done for wireless solutions by the Difficult Meter Position WG).

Basically, measuring attenuation and noise levels in a home’s electrical wiring could be achieved using a signal generator (typically a GBF) injected into the home network through a specific coupling unit. The received signal could be measured using a spectrum analyser.

Given the variety of approaches to wiring houses, particularly where there have been conversions, extensions, or refurbishments, and variation of consumer equipment which may create noise or interference, it is not possible to infer that a property type based on criteria such as age, construction type, or area, has a particular set of characteristics in terms of attenuation or noise. However, a measurement campaign in a reasonable set of houses could provide broad indications of field constraints and support an evaluation process for a GB wired SMHAN solution.

23.1.11 RecommendationsThe HAN WG recommends that a number of activities are considered;

24 The SMHAN Evaluation Criteria & Tests in the ESoDR appendix should be reviewed and updated by subject matter experts to include the necessary elements to cover both dedicated and shared (i.e. PowerLine) wired options.

25 A significant test of the available PowerLine solutions should be undertaken. Given the range of possible technologies, the diversity of housing stock and the multiple sources of interference, this has not been possible within the time available to the HAN Working Group. A realistic approach would be to measure attenuation and noise on a limited sample of GB houses in order to first estimate the house characteristics and interference levels that can be expected, and any co-existence problems that could occur.

26 Further effort should be made to take into account the findings from PLC tests and installations which have been undertaken by European utilities or telecoms operators. It should be noted that the differing wiring regulations across the EC may limit the usefulness of such information in GB, and that the requirements and use cases may be significantly different from GB.

27 A more detailed understanding should be formed of the issues relating to broadband communications services (ADSL2+ and VDSL) suffering interference from and to both Narrowband and Broadband PowerLine technologies.

28 Work with the relevant European bodies (CEN, CENELEC, ETSI) to set and impose criteria on the standards bodies who are developing next-generation standards (ITU, IEEE) such that those new

standards make allowance for the needs of communications technologies used in European smart metering deployments, particularly in a HAN context.

28.1 Other General Points of NoteA number of general topics were discussed at the HAN WG, and are worthy of note here.

28.1.1 Electromagnetic SensitivityThe HAN WG considered the Electromagnetic Sensitivity (EMS) implications of a recommendation to implement the use of wireless technology to support smart metering. It is aware of the ongoing concerns in this area, but noted that;

- There are specific provisions within the ESoDR for compliance with ICNIRP requirements in emissions

- All communications products put on sale within EU are required to comply with the Electromagnetic Compatibility Directive

- The recommended Evaluation Criteria include ‘good neighbour’ and ‘good citizen’ emissions testing and evaluation

- Generally, all wireless technologies being considered were specifically very low power as they need to support battery powered gas meters

Further work could be done in this area if there is a decision to use specific technologies, but at this stage, the HAN WG has proposed no additional activities.

28.1.2 Market MaturityThe HAN WG noted throughout, and had this reinforced by the evaluation exercise, that the HAN is a relatively new market. There are mature solutions available, but these have tended to be developed for other applications (home automation, automated meter reading, etc.) and are not necessarily a good fit for smart metering. For both wired and wireless solutions there is a preponderance of new and start up technology – and whilst some of it looks quite interesting and potentially suitable for use in an SMHAN context, if it is not available to test, or will not be available to test in the next six months – it cannot be viewed as a realistic option at this stage.

Between the new and the old, there are a number of ‘leading’ technology options. The HAN WG anticipates that the HAN market will develop into a natural monopoly or duopoly – in the same way that Wi-Fi and Bluetooth have come to dominate their particular markets. There are some barriers to this – different construction materials in different markets, different utility structures and requirements – but the common requirement remains – low cost, low power, reliable wireless equipment.

Any GB activity will contribute to developing the maturity of HAN technologies, as our deployment will initially be the largest in the world specifying a relatively sophisticated and open HAN.

28.1.3 Dedicated Wire SolutionsThe HAN WG has acknowledged that a minority of sites or consumers may require a dedicated wired approach to achieve connectivity between SMHAN Devices. The group has not undertaken any specific activity in this area, as it is likely to be installation bespoke, and within the gift of discussions between consumers and Suppliers to determine the most acceptable approach for each case.

The group considered options such as Ethernet cabling, Plastic Optic Fibre cabling or twisted pair cabling. It did not consider how to address physical connection to devices. All dedicated wired options should be capable of upper layer interoperability with Wireless or Wired SMHAN solution options.

Further work could be undertaken to improve the potential interoperability of any dedicated wiring to be used for SMHAN connections.

28.1.4 Process Governance for HAN FirmwareThe HAN WG was concerned that the ability to support Over The Air upgrades of HAN solutions was not accompanied by some view of rules and governance. Without some controls, it could present a significant challenge to interoperability unless the version of a HAN technology is known.

28.1.5 Electromagnetic Compatibility & Swedac Issue with PowerlineThe HAN WG reviewed and noted the EMCIA report on Electromagnetic compatibility, and the particular issues that could accrue for use of powerline solutions. The group further noted the issue raised by the Swedish standards body Swedac with regard to EMC and electricity meters in the 3-150KHz range.

There are proposals to review and update the standards on Emissions in this range.

28.1.6 Security ConsiderationsWhilst the group has been supported by security representatives, it has not been possible, whilst HAN technologies and issues are being identified, and security principles and requirements agreed, to do detailed assessment work on the suitability of the security of technologies or the requirements or vice versa. The HAN WG noted and endorsed the work of the Application Layer Working Group on HAN Application Layers and the security requirements, and also a lack of knowledge/material on security and wired HAN options.


29 The HAN WG recommends that any Business Processes for Firmware and Over The Air upgrades of HAN take note of the version control and governance concerns

30 The Programme (and industry) should monitor developments on the Electromagnetic Compatibility issues, particularly as wired technologies within this frequency range could be considered for the SMHAN

31 Further detailed work on HAN technology security – wired and wireless – is necessary once the security requirements, and the architectural possibilities, are clearer.

32 HAN Evaluation CriteriaThe HAN WG has developed the draft Evaluation Criteria proposed at the culmination of the ERA Local Communications Development work. The Criteria have been revised to reflect the Prospectus, the ESoDR and the development of the market. Tests for paper and bench/laboratory have been defined. The criteria have been updated to address the anticipated requirement for wired HAN technologies.

Subjecting technologies to these Evaluation Criteria will allow the Programme, Industry, Manufacturer or any procuring party to understand if those technologies are fit for purpose to use as an SMHAN in GB.

The proposed final Evaluation Criteria, with paper and laboratory tests, are attached as an appendix to this report, and proposed as an enduring appendix to the ESoDR.

HAN WG Recommendation(s):33 The present set of Evaluation Criteria remain relatively ‘sunny day’ assessments. A number of ‘rainy

day’ criteria could be developed to cover difficult premises, known interferers or challenging circumstances.

34 Conformance Testing of Directly Connected SMHAN DevicesDevices to be connected to the SMHAN are termed Approved Devices (see section 8.1). The Interoperability Testing Working Group (IOTWG) has considered the requirement for interoperability between Smart Metering System devices and has recommended that interoperability testing be undertaken by independent commercial test houses. All devices to be connected to the SMHAN will be required to pass a set of interoperability tests as recommended by the IOTWG.

In addition to interoperability tests, Approved SMHAN Devices also need to be shown to conform to the individual requirements of the base standard applicable to the SMHAN. This is usually referred to as Conformance Testing. Typically this consists of two steps:

• Pre-conformance Testing• Conformance Testing

Pre-conformance Testing helps a manufacturer to ensure that a product is ready for submitting for the full set of tests that are required to show conformance. Conformance Testing is a comprehensive, documented and audited process designed to ensure that all devices offered for sale pass a minimum set of requirements needed to operate safely and effectively according to the specifications laid down.

Conformance Testing needs to cover issues applicable to any electrical product, such as electrical safety and EMC performance. In the case of SMHAN devices these requirements will be satisfied by passing tests to the relevant European standards that will lead to the application of a CE mark. In addition, devices intended for direct connection to the SMHAN will need to pass tests specific to the requirements of the GB SMHAN. We refer to this process as Type Approval. Devices passing these tests are deemed to be Type Approved, which may be evidenced by the application of an appropriate Mark.

There are several approaches to implementing a Type Approval system. Two options that may be applicable to SMHAN devices are:

• Test House Certification• Self Certification

(a) Test House CertificationThis involves production samples of each product being submitted to an approved independent test house for testing against a series of specifications defined by the Programme. The tests are designed to ensure that any device that passes them all will be fit for purpose, in this case as a device suitable for direct connection to GB SMHANs. They will include an assessment of technical (RF or wired) performance in terms of operating range, data throughput, interference to/from other devices and error rate.

There will be a cost involved in carrying out the tests and in maintaining and policing the system.

Test House Certification can be strictly controlled and provides the highest level of confidence that devices will work properly on the SMHAN, will not cause disruption to the operation of the SMHAN and will not compromise the security of the Smart Metering System or its data.

Devices passing the tests will be permitted to have a recognisable sticker or Mark applied to them. The device manufacturer will be issued with appropriate security codes and/or procedures which will allow the devices to be Authenticated and attached to SMHANs. Consumers will be able to identify Approved devices via their Mark, and will be able to buy with confidence that these devices will work on their SMHANs.

(b) Self CertificationSelf Certification is a process whereby the device manufacturer or distributer undertakes its own testing against a set of tests specified by the Programme. If a product passes the tests then it may have the appropriate Mark applied to it.

Self Certification can include the same set of tests and pass/fail criteria as Test House Certification, but responsibility for compliance rests with the manufacturer carrying out the tests, not an independent test house. As a result, costs are lower (and are usually borne by the manufacturer) but there is a reduced level of confidence that products made available for sale have actually passed all the specified tests. Reputable manufacturers will diligently design and test their products and only apply the Mark if the product passes. But in consumer product markets not all manufacturers operate to the same high standards.

A process including the approval of Self Certification systems can be designed to minimise the chance of errors in testing devices. But the lack of separation between the organisation doing the testing and the one attempting to get the product approved means that there is always a risk that commercial pressures will affect the integrity of the testing in some cases.

Additional Conformance Protection for SMHAN DevicesIn the case of the GB SMHAN there is an additional layer of protection applying to both Type Approval and Self Certification in that devices found to cause a problem can have their Authentication permission withdrawn, preventing them from being connected to SMHANs. This could include disconnecting them if they have already been connected by turning them into Detached SMHAN Devices (see section 8.1).

However, this would only be likely to happen after devices had been put on the market and found to cause problems. It would require someone to detect a problem and trace it to a particular product. If the problem involved a security issue then the integrity of SMHANs or their data could be compromised before the devices concerned can be removed from SMHANs. Poor PR could result if significant numbers of devices have been purchased by consumers before a problem is identified, and these devices subsequently cause problems or are disconnected through having their security permission withdrawn.

Reaching a DecisionThe Programme will need to decide which of the above approaches (or another approach) to adopt for Conformance Testing of devices to be connected to the SMHAN. This decision will need to be based on an assessment of at least the following criteria:

• Degree of control over SMHAN devices required by the Programme• Depth of security that is provided to protect against Authorised devices carrying out unauthorised

actions

• Risk that a poorly-designed product could compromise the security or operation of the Smart Metering System

• Sensitivity to costs involved in testing SMHAN products• Potential impact on consumers of problem devices being disconnected from SMHANs

In reaching a decision it should be noted that it is difficult to move to Test House Certification from a Self Certification regime, whilst it is not so difficult to move the other way.

The HAN WG has considered the options for Conformance Testing and whether sufficient information is available to make a firm recommendation of the appropriate approach to be taken for devices to be directly connected to the SMHAN.

A safe approach would be to begin with Test House Certification whilst retaining an option to move later to Self Certification once real-world experience is built-up through system rollout.

Based on the information currently available the WG does not feel that either Test House Certification or Self Certification can be rejected as a valid approach. Each has the potential to meet the requirement for Conformance to an SMHAN specification, provided that it is implemented and policed effectively.

Once it becomes clear which technology or technologies will be selected for the SMHAN then an evaluation against the above criteria should enable an appropriate choice of method to be made.


35 The HAN WG recommends that any subsequent Programme activity on Interoperability Testing take account of the options for HAN Conformance testing as described in this document

Appendix A - HAN Evaluation ExerciseDuring May and June 2011, following an exercise by the group to identify and document potential HAN solution technologies, a request for information in the form of a questionnaire was sent to over 20 representatives of individual technologies.

The intention of the exercise was to test the suitability of the Evaluation Criteria and the questions used to assess compliance with these criteria. It also served to provide information on individual solutions, and to establish working relationships between the Programme and technology providers.

All of the materials of the exercise – questions, contacts, responses & summary of answers – are published on the HAN WG site at this page: https://sites.google.com/site/smdghanwg/evaluation-exercise

The evaluation criteria in the appendix below, and the proposed questions, have been amended as a result of this exercise.

The HAN WG was pleased to note that all the perceived ‘leading’ options for wireless HAN options responded to the questionnaire, albeit with some issues on completeness or timeliness. Other points of note:

- No responses were received from wired solutions- Most, but not all, technologies provided answers that highlighted one or more key gaps in their

current offerings when reviewed against the SMHAN requirements.- These gaps were of concern to the group as they appeared to be mainly functional rather than

commercial. It might be possible to resolve some of these gaps through discussion and clarification.

The illustration below reflects the position of the group on the Evaluation Exercise.

https://sites.google.com/site/smdghanwg/evaluation-exercise

Evaluation Exercise Review

No Suitable Technologies- requirements/criteria too high/too hard- time to reach required level is unacceptable or unlikely

Many Suitable Technologies- Requirements & Criteria are too general/too easy- Lots of potential HAN choices could result in confusing options for Customers and Suppliers

Some Suitable Technologies- Requirements generally suitable- Document any gaps or issues- Understand potential market HAN technologies today/future- Recommend process for delivering certification

Programme to revise requirements to make them accessible to existing solutionsHAN WG Recommends certification to ensure solutions are capable of meeting requirements

Programme to revise requirements to narrow optionsHAN WG Recommends a selection activity to reduce number of options

Programme to address any gaps or issues in requirements/criteria

Depending on number/type of technologies deemed suitable, and where the issues are:- HAN WG Recommends a selection activity to reduce number of options- HAN WG Recommends certification to ensure solutions are capable of meeting requirements- HAN WG Recommends one or two options for relevant Physical variants (that can support recommended App Layer)

Next Steps

As a result of reviewing the initial content from the exercise, the group notes that the position is as anticipated – ‘Some Suitable Technologies’. Detail of the findings of the group can be found at the link provided above.

More importantly, as noted above, the group concluded that the mechanism of the evaluation criteria, and associated tests, could be an effective tool for either the specification of fit for purpose HANs, or for selection of HANs.

Appendix B - HAN Testing Exercise ReportIn June 2011, the HAN WG, with the support of the Smart Energy Special Interest Group (SESIG) of the Technology Strategy Board, undertook some laboratory testing of existing HAN technologies.

Due to the restricted time and funding available, the tests were fairly simple, and limited to wireless options only. 20 technologies were invited to provide samples for testing, but only 4 were able to participate, mainly due to time pressures. The four technologies participating were Z Wave, ZigBee @ 2.4GHz, KNX and EnOcean.

The tests carried out were;- Basic Interoperability – can the boards see and connect to each other- Power Consumption – for peak activity and for dormant operation- Path Loss/Attenuation – to help determine the potential range of the radios- Immunity to interference – how do the radios cope with known sources of interference- Transmitter Performance – does the radio operate as specified with regard to emissions

Not all of the tests were possible for all of the boards provided as some samples did not have the appropriate documentation.

Key lessons learnt from this exercise;- Time, funding and planning is fundamental – this testing is new and fairly unique. The rigours

applied to some standards and practices may not be directly applicable to HAN technologies- It might be necessary to divide the testing between specialist laboratories- Resource from the group (Programme/Industry etc.) commissioning the testing needs to be on hand

to advise the technology providers and the test facilities where questions arise- Products for testing, in the form of development boards or otherwise, were not generally available

for the technologies we contacted – only a couple of technologies were able to respond with ‘ready to go’ equipment. It should be noted that the timescale for this round of testing was extremely tight.

The group concluded that the requirements for further testing should be;- To generate a fully detailed test specification for each test, to ensure sample providers and test house

know precisely what tests will be carried out and how they will be performed:o each test should be designed to confirm one or more key SMHAN performance criteria, and

to allow absolute and relative performance of devices to be assessedo test specifications should include specific details of device configuration (e.g. profile) to be

usedo tests should include 'over the air' measurements using representative interference/multipath

environments- Allow more time for discussions with sample suppliers and test house, to ensure samples provided

are:o representative of devices that will be deployed in GB SMHANso capable of performing the tests requiredo fully documented

- Provide adequate resources for sample sourcing, test specification preparation, test house interactions, testing and report writing.

- Tests should deliver results that are easily understood by non technical people if at all possible. For example, if it is possible to work on real product messages rather than test packets on a radio, then this is preferable..

- Tests should ideally be carried out using real end products, except where the manipulation of the device required to perform that test makes this practically difficult.

- Vendors of hardware should be available (and allowed to be available) to support the tests to ensure that results are not affected by lack of knowledge of the technology or the hardware, or documentation errors.

o However, vendors of hardware should NOT be allowed to perform the tests themselves or change results obtained by the independent test house.

- Wired testing of over-the-air performance should only be used in parallel with real radio tests, to establish a base line or theoretical ideal.

- Tests performed on physical radio only should ideally be complimented by tests performed using a full application and network stack.

Summary of Results from Initial Testing

Test Technology A Technology B Technology C Technology D

Basic Interoperability

Not Tested Not Tested Not Proven Not Tested


Current Consumption3

Dormant: 43mA Active: 43mA

Dormant: 0.5mA4

Active: 0.7mA to 31mA

Dormant: 8.8 to 11.2mAActive: 16.6 to 43.8mA

Dormant: 29.6mAActive: 31.5mA

Power Consumption - Dormant

Controller (230 VAC): 340 mWDevice (230 VAC): 1.26 W

Controller (230 VAC): 71 mWDevice (6.0 VDC): not measurable

(3.25 VDC): 36.5 mW(5.0 VDC): 44.5 mW

(9.0 VDC): 268 mW

3 As most of the samples were provided in the form of Development Boards, the current and power consumption figures are not necessarily reflective of final production equipment

4 Single sample only


Power Consumption – Active

Controller (230 VAC): 341 mWDevice (230 VAC): 1.26 W

Controller (230 VAC): 194 mWDevice (6.0 VDC): 4.3 mW / 188 mW (2 samples)

(3.25 VDC): 138 mW(5.0 VDC): 82.9 mW

(9.0 VDC): 284 mW

Path Loss - Packet Error Rate

Not possible GoodSee Packet Error Graph

GoodSee Packet Error Graph

GoodSee Packet Error Graph

Path Loss – Link Failure Level

Not possible -102.7dBm -96.6dBm -101.6dBm


Immunity to Interference(Wanted/Unwanted Ratio – In Band)

Not possible Poor-0.2dB

OK12.2dB

Poor3.7dB

Immunity to Interference(Wanted/Unwanted Ratio – Out of Band)

Not possible Good80.8dB

Good86.2dB

Good78.7dB

Transmitter Performance – Carrier Power

Not possible OK-21.8dBm

OK8.5dBm

OK-5.7dBm


Transmitter Performance – Spurious Emissions Margin5

Not possible Poor-12.6dB

Good>18.3dB

Good>30.1dB

Note that the first test was not possible for any technology as for all but one technology, the samples provided were from one manufacturer only. For the technology provider who provided samples from different manufacturers it was not possible to perform the test.

Figure Packet Error Rate

Appendix C - HAN ESoDR– Evaluation CriteriaThis document has been written with the intention of it being an enduring, change controlled element of the ESoDR documentation.

This appendix presents additional technical and commercial criteria to support and inform the ESoDR HAN requirements. These criteria have been written to allow the Programme or Industry to use them to support any future selection or evaluation exercise for candidate HAN technologies.

5 Worst case spurious emission margins measured against the appropriate EU harmonised test standard for that technology

1. ConventionThe table below uses the following column headings

- Ref – a unique reference number for the criteria, these are not sequential but will be reorganized prior to publication of the final draft set of criteria

- Criteria – a description of the individual criteria- Wired & Wireless – a number of criteria will only apply to radio or wired solutions6

- ESoDR/Security – reference to a Programme document containing requirements. e.g. S.HAN.02 for the security requirements, or ES.11 for the ESoDR

- Expectation – what do the HAN WG anticipate as being an indicator of compliance with the criteria – can include any comments or expectations of test

As a general principle, all criteria, as appropriate, should state either;o ‘under normal operating circumstances’, oro ‘typical usage’ etc.

2. Evaluation Criteria

Ref Criteria Wired & Wireless

ESoDR/ Security

Expectation

General & ESoDR Requirements

6 An assumption to note here is that wired in a HAN context is expected to be a power line based technology. The use of dedicated wiring is expected to be very limited


ESoDR/ Security

Expectation

1.1 Under normal operating circumstances, there is no expectation for customers to take any action to maintain the operation of the SM HAN7

Both IM.04OP.01

Is mainly a product characteristic and is expected to be resolved through development of the market

Test through written questions

Qualitative results are expected

1.2 The SM HAN should not add unnecessary complexity or time to commissioning, binding or pairing devices

Both IM.11 Security Requirements will have a bearing here

Product characteristic

Test through written questions

Qualitative results

Expectation that SM HAN contributes less than 10 seconds to overall process

7 This is for technical operations – Customers are expected to interact with the HAN to pair/bind new devices


ESoDR/ Security

Expectation

1.3 Minimise number of site visits and customer calls to address SM HAN issues

Both Depends on quality of product

Test through evidence from other relevant deployments

1.4 Percentage of GB homes covered by this solution with no additional equipment

Both Test through written questions and evidence based responses

Derive coverage from other tests and known parameters (e.g. building stock, construction types, meter locations)

Linked to deliverable from Difficult Meter Positions WG

1.5 Physical dimensions for SM HAN solution components to be suitable for use in metering and related products and the environmental conditions in which these are expected to operate

Both Test through provision of reference design/schematic

Circuit board and antenna (for wireless)


ESoDR/ Security

Expectation

Interoperability

2.1 Is an Open Standard as defined by the European Union, or can demonstrate a clear path to approval as an Open Standard

Both HA.01IN.03

See below for definition of an open standard

Request statement of compliance or planned compliance (including timed delivery)

2.2 Genuine choice and competition between silicon vendors

Both Expect a minimum of three independent silicon vendors, although other approaches could be considered if criteria 2.1 is demonstrated

Test through provision of a statement of compliance


ESoDR/ Security

Expectation

2.3 Interoperable solutions from a minimum of three providers can be tested today8

Both HA.05 Today – is at the point of undertaking the testing

Non technical test is the availability of products to test

Technical test will, where possible, link three chips (from different providers) together to demonstrate the most basic interoperability

2.4 Support for a minimum of 8 HAN Devices in a network9

Both HA.19 Non technical test to be a request of proof of compliance within the specification

Non technical to demonstrate maximum number of devices in a practical implementation10

8 This criteria will be tested non-technically for ‘pre-qualification’, but will also form part of the technical evaluation to provide additional assurance of a critical requirement

9 This could be influenced by HAN WG options paper on scope of the HAN, but essentially provides for 2 Meters, 1 IHD, 1 Comms Hub and 4 other devices – repeaters, booster, microgeneration meters etc.

10 For enduring, product based testing, this should be considered for technical testing


ESoDR/ Security

Expectation

2.5 Support for suitable SM HAN Application Profiles

Both HA.07HA.15IN.03OP.02

Request details of support

Power

3.1 Power : ‘active’ Both IH.02OP.04

Current consumption, in Joules while transmitting one secured half hourly read of usage data from a meter


ESoDR/ Security

Expectation

3.2 Power : ‘peak’ Both IH.02OP.04

Peak current, in milliAmps (mA), during a transmission 11

3.3 Power : ‘dormant’ Wireless IH.02OP.04

Current consumed, in microAmps (uA), while the HAN solution is inactive / asleep awaiting the next transmission event

11 Or milliWatts for Powerline technologies


ESoDR/ Security

Expectation

3.4 Support for battery powered nodes (i.e. have an ability to go into a ‘sleep’ mode)

Wireless GS.03HA.11

Request for statement of compliance

Data Performance

4.1a Data Transmission Speed Wireless DS.2HA.07

Time taken to transfer a block (/file) of 10KBytes of data from one device to another device 10 metres (in free space) apart (test to be done using the normal modulation used/specified by the standard)

Also perform the test for 300Kbytes of data


ESoDR/ Security

Expectation

4.1b Data Transmission Speed Wired DS.2HA.07

Time taken to transfer a block (/file) of 10KBytes of data from one device to another device 10 metres apart (test to be done using the normal modulation used/specified by the standard)

Also perform the test for 300Kbytes of data

4.2 Robustness Both ES.11HA.09

To be tested by monitoring the level of success for transmitting a set number of standard messages.12

To be completed for a number of test environments (see 5.3)

12 For Example – simulate the transmission of 10,000 messages (or other suitable number to be agreed) in a standard environment – how many complete first time, how many retries are needed, how many messages never complete.


ESoDR/ Security

Expectation

4.3 Supports Acknowledgement of packets and retries (not application)

Both Request statement of compliance

Performance

5.1a Point to Point Range Wireless Physical point to point range (in metres) and link budget (in dB) of the radio in free space, tested with best in class radios used for the standard being tested, based on an example maximum 1% PER (Packet Error Rate), transmit power set within regulatory limits for that frequency/modulation and receive sensitivity and antenna reflecting normal commercial use of the radio in SMHAN.


ESoDR/ Security

Expectation

5.1b Point to Point Range Wired Performance is greater than or equal to a given threshold for a certain percentage of socket pairs in a room of “x” square metres. Based on maximum 1% PER (Packet Error Rate), transmit power set within regulatory limits for that frequency/modulation and receive sensitivity and antenna reflecting normal commercial use of the radio in SMHAN

5.2a Point to Point Range Wireless As per 5.1a, but with tests conducted at an application level using a standard application profile to be used in SMHAN, thus accounting for standard network and application level mechanisms for improving robustness of message delivery and accepting x% (to be defined, might be 0) loss of application level messages.

5.2b Point to Point Range Wired As per 5.1b, but with tests conducted at an application level using a standard application profile to be used in SMHAN, thus accounting for standard network and application level mechanisms for improving robustness of message delivery and accepting x% (to be defined, might be 0) loss of application level messages.


ESoDR/ Security

Expectation

5.3 Defined set of tests in a variety of simulated radio location scenarios.

Scenarios to be provided by Difficult Meter Positions Working Group

Both Links to 1.4

Potential for some tests to be defined to cover post installation, temporary or permanent, environmental changes

5.4 Vulnerability to signal interference Both Request documentation to demonstrate compliance and techniques

5.5 Ability to cope with signal interference

Both Can investigate with other products;- within license exempt bands for wireless- alternative PLC technologies in the same spectrum range for wired

Technical tests to be defined to challenge solutions against known interferers


ESoDR/ Security

Expectation

5.6 ‘Good Neighbour’ test – the solution should not materially affect other networks

Both HA.22 Technical tests to assess coexistence with:- Other SM HANs in

neighbouring properties- Other HANs or other networks

operating within premises

5.7 “Good Citizen” test – the solution should not materially affect other services

Both Powerline solutions have potential to interfere with e.g. amateur radio and broadband services. Test should be devised with this in mind.

5.8 Provision of diagnostic information for SM HAN

Both Request statement of compliance


ESoDR/ Security

Expectation

Security Requirements

6.1 To be added when available from Security Team

HA.02HA.16IM.10

Initial desktop testing to be carried out by Programme Security Team

Future Flexibility


ESoDR/ Security

Expectation

7.1 Support for upgrades of SM HAN firmware without direct physical connection

Both HA.12IM.02OP.07

Request statement of compliance with criteria

7.2 Support for firmware upgrades in SM HAN Devices

Both As above

7.3 Existing nodes/devices are not stranded as a result of upgrades to the solution

Both Request statement of compliance of criteria and some test scenarios – recovery if device was not present when upgrade took place


ESoDR/ Security

Expectation

7.4 Longevity of frequency – availability and usability

Wireless Request statement of compliance of criteria

7.5 Longevity of solution technology Both HA.20 Request statement of compliance of criteria

Cost


ESoDR/ Security

Expectation

8.1 Typical bill of materials cost per SM HAN enabled device

Both Request indicative costs based on a known volume

8.2 Total Cost of Ownership – including power consumption

Both Request indicative cost against a specific scenario of service and usage

Technology Maturity


ESoDR/ Security

Expectation

9.1 Use in equivalent smart metering deployments

Both Request data to identify and quantify implementation

Request utility/manufacturer references

9.2 Use in analogous applications – home automation, micro generation etc.

Both Request data to identify and quantify activities

Request industry references

9.3 Clarity of development strategy Both Request for development roadmap to show potential significant changes and anticipated product lifecycles


ESoDR/ Security

Expectation

9.4 Capacity in vendors to meet smart metering demands – minimum of 4 nodes per home

Both Request statement of capacity

5 year deployment to 25 million homes

9.5 Availability of non-metering products that could be relevant to smart metering – e.g. thermostats, display devices

Both Request data to identify and quantify products

3. Evaluation QuestionsThe following questions are recommended to be provided to representatives of candidate HAN solution technologies to inform any selection or evaluation process.

Evaluation Criteria Ref

Question

Q1.1(a) Is your SMHAN solution easy to maintain? (i) Does your system include facilities for remote maintenance (e.g. an end-user "assistant" to

allow consumers to solve simple problems). (ii) Please describe any specific features of your solution that support your answer.


Question

Q1.1(b) Please explain:(i) How these maintenance features work(ii) How they have been used in existing products that have been rolled-out, for smart metering

or other home related applications(iii) Please provide references of implemented systems being maintained using the above features

Q1.2 Is your SMHAN solution easy to commission?(i) Please provide an outline of your installation and commissioning process, including a

description of the skills required to complete an installation and any pre-install configuration required prior to the installation visit

(ii) Describe your approach to field upgrades (e.g. to add a new SMHAN device) and indicate whether appropriate upgrades can be carried out by the end user

(iii) Please describe any features of your solution that support your answer.Q1.3(a) (i) Please describe your approach to system reliability and maintainability, stating calculated and

measured MTBFs and MTTRs where appropriate for a typical SMHAN installation comprising four connected devices.

(ii) Please describe the specific features of your solution that increase the reliability of your networks and reduce support effort.

Q1.3(b) (i) With reference to equivalent smart metering or home area networking deployments please provide data on site visits and customer calls required to maintain deployments.

(ii) If appropriate please provide references for utility customers who may have this data.Q1.4 (i) Please provide your assessment of the proportion of GB homes that could be covered by your

HAN solution without a need for additional equipment (e.g. repeaters)(ii) Please provide evidence (references) to results of tests carried out in buildings representative

of GB housing stock, including multi-occupancy dwellings. Note: A standard GB SMHAN installation will include an Electricity Meter, Gas Meter, In-Home Display and a Comms Hub

(iii) Please describe which types of GB homes your solution could and couldn’t cover (again without additional equipment) and explain the reasons.

(iv) Please provide references to supporting material on other in-building tests which provide further evidence of your system's capability.

Q1.5 (i) Please provide the physical dimensions (length, width, height) of a typical reference design or module that might reasonably be used in a SMHAN device. This should include all components necessary to operate the SMHAN communications, including antenna, microcontroller and radio.

(ii) Please describe any specific implementations you may have for tamper-resistant antennas that may be mounted externally to a meter enclosure, including details of the increase in transmission range that they provide

Q2.1(a) (i) Is your solution based on an Open Standard? (ii) Please provide evidence, including relevant standards references, or if you have a roadmap to

become an Open Standard please explain the schedule and plan for this.Q2.1(b) Is the development of your standard managed by a not for profit organisation? If so, please identify

the organisation and provide evidence of its status. Q2.1(c) Does your IPR policy include RAND licensing that can be availed of by anyone?


Question

Q2.1(d) Are your specifications available for everyone to study? Is there a cost involved? Please provide details of how to access your specifications.

Q2.1(e) (i) What mechanism exists for stakeholders to contribute to the development of the specifications?

(ii) Is there a requirement to become a member of an Alliance or equivalent, and if so, what is the cost?

(iii) Is public review part of the decision-making process? Q2.2(a) How many different commercially available platforms support your SMHAN solution?

Please list them including manufacturer’s name and contact details (e.g. web site) and provide evidence of their commercial availability, or a roadmap for availability.Note: By “different”, we mean that platforms use different silicon and software vendors/solutions in their designs

Q2.3(a) (i) Please list the independent solutions available and provide evidence of the existence of at least 3 different interoperable solutions from 3 different providers, ideally publicly available and independently verifiable.

(ii) Please explain how interoperability of different manufacturers' solutions is tested and verified (if this makes use of a Golden Unit, state who produces and maintains it)

Q2.3(b) (i) What is the established certification process to assess conformance of products to your specifications?

(ii) Please list the names and locations of independent test and certification laboratories that are set up to test products designed to your standard

Q2.4(a) What is the maximum number of devices that can be connected in a single self-contained network using your solution? (i.e. without the use of gateways or bridges to connect separate subnets or networks)?

Q2.4(b) (i) What is the recommended maximum number of devices in a single smart metering HAN using your solution?

(ii) Please explain the characteristics of your solution that impact the maximum number of devices in a smart metering HAN.

Q2.5(a) What smart metering HAN application profiles or protocols does your solution support?Please provide details including as appropriate links to appropriate standards and specifications.

Q2.5(b) Please provide evidence of the use of your solution including the aforementioned application profile or protocols in other smart metering HAN deployments.

Q2.5(c) Please provide evidence of how this application profile or protocol supports GB HAN requirements, including if applicable any roadmap.

Q3.1 For a typical SM HAN device using your solution, what is the expected energy consumption, in Joules, from wake up/activate to sleep/deactivate, to transmit one secured half hourly read of usage data from a meter?Note: Please specify what value the transmission power is set at to send this data (GB maximum regulatory limit or lower).If this response differs depending on individual implementations or environment/external conditions please explain the likely range of answers for different implementations.


Question

Q3.2 For a typical SM HAN device using your solution, what is the expected peak current in milliamps (mA) during transmission of a packet of data? Note: Please specify under which reference voltage the solution is operating. If this response differs depending on individual implementations please explain the likely range of answers for different implementations.

Q3.3 For a typical SM HAN device using your solution, what is the current consumed, in microAmps (uA), and the average active energy consumption, in Joules per hour while the HAN solution is inactive / asleep awaiting the next transmission event.Note: If this response differs depending on individual implementations please explain the likely range of answers for different implementations.

Q3.4 Does your solution support battery powered nodes? Please explain how. Please explain if the battery powered nodes have specific characteristics differing from mains powered nodes.

Q4.1(a) What is the expected application data throughput for your solution in a point-to-point transmission? Note: Please include the overhead of any application or networking protocols, security and any acknowledgement mechanisms.

Q4.1(b) What is the expected time taken to transfer a block (/file) of 10KBytes (Kilobytes) of smart metering data from one device to another device 10 metres (in free space) apart in the SMHAN? Note: Please state your assumptions concerning the overhead of signalling/control data that your system adds to the data payload before transmission

Q4.1(c) What is the expected time taken to transfer a block (/file) of 300KBytes (Kilobytes) of smart metering data from one device to another device 10 metres (in free space) apart in the SMHAN?Note: Please state your assumptions concerning the overhead of signalling/control data that your system adds to the data payload before transmission

Q4.2(a) Please describe all mechanisms used by your solution to ensure robust communications between devices, and refer to any case studies or evidence to show robustness of your solution.Note: Please list the mechanisms that apply at application, network and physical layers within your protocol and refer to specification documents as appropriate

Q5.1 (i) What is the expected point-to-point range of your radio in free space, based on maximum 1% PER (Packet Error Rate), transmit power set within EU regulatory limits for that frequency/modulation and receive sensitivity and antenna reflecting normal commercial use of the radio in SMHAN?

(ii) Please provide evidence and results of independent testing in support of the range figures you quote

Q5.2 (i) Are there any mechanisms in your solution that would extend the point-to-point range beyond that normally expected by the physical medium (e.g. network retries to improve error rates, use of repeaters or range extenders)?

(ii) Please explain how these mechanisms work and the measured impact that they have on operating range at a given BER

Q5.4 (i) Please identify any potential interferers with your solution and how they could impact communications.

(ii) Please list and quantify the expected impact over the 15 year lifetime of the SMHAN system of:(a) co-channel (in-band) interferers(b) adjacent channel (out-of-band) interfererswhich exist or are expected to exist in GB homes over the system lifetime


Question

Q5.5 (i) Please describe any mechanisms available to your solution for dealing with potential signal interference, with reference to appropriate specification or standards documents.

(ii) Please outline your proposal for dealing with any SMHANs which fail in the field as a result of increasing levels of interference in your chosen frequency band from other services during the 15 year lifetime of the system

Q5.6 Please describe how your system design ensures that your solution does not interfere with or otherwise materially affect other networks or services using the same or different frequencies or physical media.Note: Please include in your analysis both existing networks and projections for future networks, where details are available

Q5.8 Please describe the information provided by your solution to assist with the diagnosis or analysis of SMHAN network connectivity and performance (e.g. signal strength, data error rate).

Q7.1a (i) Does your solution support the upgrade of firmware on SMHAN devices without physically connecting to the device (e.g. using a radio link).

(ii) Please describe the mechanism and refer to any specifications or standards as appropriate.(iii) If your system does not support remote upgrade, please describe how upgrades are carried

out and the effort involved in achieving thisQ7.1b (i) If existing, please provide example of products (smart metering or home applications) that

were actually upgraded on the field without manual intervention.(ii) Please describe the upgrade purpose, size, number of products affected, and any reference to

the utility or customer of the product.Note: Where appropriate, please provide a reference to a utility that uses your system and can provide such data (on a confidential basis if necessary)

Q7.3 (i) Please describe the mechanisms in your solution for ensuring that existing nodes/devices in the smart metering HAN are not stranded as a result of a firmware upgrade.

(ii) Please list separately the mechanisms for dealing with:(a) a network where devices may have more than one firmware version(b) a situation where a remote firmware upgrade fails on some or all devices

Q7.4 What is your expectation for the future availability and usability of the physical media (e.g. radio frequency) used by your solution? Your response should consider any likely threats and present arguments to support the continued use of your solution into the future.

Q7.5 (i) What is your expectation for the future availability of solutions and platforms?(ii) Please provide examples of (public domain) future product roadmaps from suppliers of your

solutionQ8.1 What is the typical bill of material cost for a manufacturer to add your solution to a SM HAN device,

inclusive of any microcontrollers required to run a networking stack and application protocols, transceivers, antenna, crystals etc.? Please consider a mains powered device (no battery needed). Note: Please use 1 million units as a base line for your answer and if there is likely to be a range of answers please provide this range and an explanation of what determines the lower and upper limits.


Question

Q8.2(a) Please provide your assessment of the total cost of ownership of your solution in an Electric meter over 15 years of usage, including initial BOM cost, ongoing power consumption, device/module replacement etc.Note: Please base your answer on an electric meter that is always available for real-time communications and which sends a packet of usage data every 5 seconds.You may assume the cost of energy remains constant at 10p per KWh during the lifetime of the system

Q8.2(b) Please provide your assessment of the total cost of ownership of your solution in a Gas meter over 15 years of usage, including initial BOM cost, ongoing power consumption or battery replacement, device/module replacement etc.To simplify calculation, please consider that the battery consumption is dedicated to the HAN communications (i.e.: no valve operations, no measurements microcontroller sharing the battery). Please base your answer on a Gas meter that communicates to send a packet of usage data every 30 minutes.You may assume the cost of energy remains constant at 10p per KWh during the lifetime of the system

Q9.1(a) Please provide case studies or evidence of the use of your solution in equivalent smart metering deployments. Note: Where possible, please include references to numbers of devices and contact information at energy suppliers/utilities.

Q9.2 Is your solution applicable to analogous applications outside of the current SM HAN deployment? If so, please identify analogous markets where there has been significant usage of your solution, providing evidence in the form of case studies or references to manufacturers, product announcements etc.

Q9.3 Please provide a roadmap for your solution, clearly showing planned and ongoing major developments with timescales for completion.

Q9.4(a) Please provide an estimate of how many nodes using your solution were shipped in 2009 and 2010.

Q9.4(b) Please describe the impact on capacity for vendors of your solution should they have to deliver 100 million additional nodes for use in GB SM HAN deployments over approximately 5-6 years (from 2014 to 2019).

4. Evaluation TestsThe following tests are recommended to be carried out on suitable sample equipment provided by representatives of candidate HAN solution technologies to inform any selection or evaluation process.

To ensure that tests deliver the answers required it is proposed that the tests are based on the following principles:

- Tests should deliver results that are easily understood by non technical people if at all possible. For example, it is preferable for testing to be performed using real SMHAN messages rather than test packets when performing tests on a radio.

- Tests should ideally be carried out using fully representative (deployable) products, except where the manipulation of the device required to perform that test makes this practically difficult.

- Where possible, all tests on radio performance should be performed using an ‘over-the-air’ connection (taking full account of any variations in antenna performance in different orientations). Performance measurements using wired (radio) connections should only be used where it is necessary to establish a base line or theoretical ideal.

- All tests of radio performance should be made using the agreed application profile and active network stack software (incorporating appropriate retry/retransmission mechanisms) to ensure tests are representative of performance in real SMHAN environments.

- Performance tests should use one of the following standard tests conditions:(a) ‘Nominal’ radio environment (no interference or multipath, nominal radio path loss), and(b) ‘Challenging’ radio environment (representative interference and multipath, higher radio path loss)13

- Tests should be performed by an independent test house, supported by (but not influenced by) equipment suppliers.

The following tests are proposed, where appropriate linked to the Evaluation Criteria detailed above:

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Test Evaluation Criteria

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Proposed Tests Notes

1 Interoperability 2.3 Perform interconnection tests between devices from different vendors

Tests to be performed using full range of features and modes that are mandated to support SMHAN functionality.

This is largely a software test activity conducted using the ‘nominal’ radio environment.

If appropriate test equipment exists that can simulate other network elements, testing could be performed using this, based on defined test scripts. An alternative is the use of ‘Golden devices’

2 Multi-device support

2.4 Perform a functional test using a network containing the maximum number of nodes

Tests should ensure that all devices are communicating on the network, with representative data loading.

Tested using the ‘Nominal’ radio environment.

13 Further work is required to define these environments. Although adding interfering sources to an over-the-air test is relatively easy, introducing representative multipath fading is much more difficult. Cabled (wired) tests may be required to separately assess the effect of multipath on the technologies being tested.

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3 Power consumption

3.1 (‘Active’)

3.2(‘Peak’)

3.3 (‘Dormant’)

Measure power consumption when network is operating in a representative mode

Where evaluation is performed on an example radio module which is supported by (for example) an evaluation board, it shall be possible for the radio module to be decoupled from the evaluation board to allow power measurements of (just) the radio module to be made.

Measuring the profile of the power consumption for completion of representative activities over a representative time cycle (e.g. 1 hour) would provide the clearest way of evaluating different technologies – this would show the variation in power over the full sleep-wake-transmit-sleep cycle. In addition it would highlight any peak current demands that are particularly relevant for gas meter battery applications.

Tested using both the ‘Nominal’ and ‘Challenging’ radio environments.

4 Data throughput 4.1 (data throughput),

4.2 (robustness)

Measure time taken to transfer a block (/file) of 10 kB and 300 kB of smart metering data from one device to another device, and perform data comparison to detect errors/lost packets etc.

Tested using both the ‘Nominal’ and ‘Challenging’ radio environments – the latter would provide a good measure of system robustness.

Tests should also be carried out at an ‘application’ or end product level to get information on real application data throughput with all protocols and overheads included

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5 Range 5.1, 5.2, 5.3 Physical point to point range of the radio in free space

Tested using an interference- and multipath-free radio environment, with radio transmit power conforming to regulatory limits and receive sensitivity and antenna reflecting normal commercial use of the radio in SMHAN.

Transmitter set to transmit test messages: ‘Message Error Rate’ (number of dropped application messages) measured for various equipment spacings14. Full SMHAN application profile to be used to allow retransmissions (etc.).

Range to be measured in free space (ideally directly outdoors), and in a number of representative building environments.

Range in free space should ideally be tested directly outdoors in a large open area, but if a suitable lab test is possible and proven to be accurate this could be used.

It may be useful to record signal quality measurements such as LQI, RSSI.

14 The intention here would be to quantify performance vs. range and allow this to be plotted to allow different technologies to be assessed against each other

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6 Immunity to interference

5.5 Functional and performance tests under different interference conditions

These tests will use various ‘challenging’ radio environments to assess the impact of both ‘co-channel’ (in-band) and ‘adjacent-channel’ (out of band) interference on normal network operation.

Interference scenarios to be based on likely ‘real world’ SMHAN environments, using real or simulated interference sources.

Interference sources to include likely devices to be found in the home, including Wi-Fi networks, other ‘HAN’ type networks, microwave ovens, video senders, domestic entertainment devices and mobile devices (in various combinations). In addition, possible interference from sources outside the home environment (radio networks and other SMHAN networks, for example) will also be included.

Sensitivity to interference from one type of interferer, and interferers acting together, to be investigated.

Impact on functionality and data throughput to be evaluated.

7 Transmitter spurious and noise

5.6 Measurement of transmit power level, and noise and spurious generated

The data recorded will allow an assessment of the likely power, noise and spurious generated by one SMHAN, and (in aggregate) of multiple SMHANs operating in close proximity.

8 HAN co-existence

5.6 Technical tests to simulate coexistence with:(a) Other SM HANs in neighbouring properties(b) Other HANs or other networks operating within premises

This is a ‘Good Neighbour’ test, verifying that the solution does not materially affect other networks.

Tests will be conducted to assess the impact of:(a) Multiple networks for the technology being tested within range of one another(b) The SMHAN on possible ‘victim’ devices or networks in the operational band (e.g. the effect of the SMHAN on an active Wi-Fi___33 network)

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9 Support for upgrades of SM HAN firmware

7.1 Perform ‘over the air’ software update and ensure device communicates and functions correctly after update has been completed.

Principally a software test but performed using both the ‘Nominal’ and ‘Challenging’ radio environments to verify robust operation in real-life environments.

Documents

HAN Select Options_Supporting Document_Stage 12