105 Rural-Remote Overview

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Rural and remoteOverview

February 2015

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Small Cell Forum works to accelerate small cell adoption to change the shape of mobile networks and maximize the potential of mobile services.

We are not a standards organization but partner with organizations that inform and determine standards development. We are a carrier-led organization. This means our operator members establish requirements that drive the activities and outputs of our technical groups.

Our track record speaks for itself: we have driven the standardization of key elements of small cell technology including Iuh,FAPI/SCAPI, SON, the small cell services API,TR-069 evolution and the enhancement of the X2 interface.

At the time of writing, Small Cell Forum has more than 140 members, including 68 operators representing more than 3 billion mobile subscribers 46 per cent of the global total as well as telecoms hardware and software vendors, content providers and innovative start-ups.

This document forms part of Small Cell Forums Release Five: Rural & Remote that considers the opportunities and perceived barriers associated with the deployment of small cells in rural and remote scenarios, including disaster recovery, military installations, as well as verticals such as oil and gas, maritime, aviation and automotive.

The Small Cell Forum Release Program has now established business cases and market drivers for all the main use cases, clarifying market needs and addressing barriers to deployment for residential, enterprise and urban small cells.

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Report title: Rural and remote small cells Issue date: 02 March 2015 Version: 105.5.1

Scope

Small cell technologies are coming of age thanks to scaling of deployments in residential, enterprise and now urban markets. These maturing technologies can also be applied to a diverse range of rural and remote use cases that may not otherwise be viable using traditional deployment approaches. Small cells are well suited to deployment in rural villages, remote industrial sites, on transportation, as well as temporary networks for public safety, humanitarian and special events. This document provides an overview of Small Cell Forum outputs that relate to the opportunities for operators to use small cells in rural and remote deployments


Executive summary

The mission of the Small Cell Forum is to accelerate adoption of small cell technologies across a range of use cases: Residential femtocells were the lead market which proved that cellular base stations could be cost reduced and made to be consumer deployable. Enterprise then scaled that to multiple cells with on-site gateways for wider in-building coverage and IT system integration. Urban then takes these into public spaces and outdoors to enhance capacity and app performance whilst interworking with existing macrocell coverage.

Our rural and remote theme represents a diverse range of additional uses for small cells, seeded in part by maturing of technologies and growing economies of scale in the other market segments. As mobile connectivity becomes ever more valuable in our everyday lives and workplaces, so the need to extend coverage beyond densely populated areas grows. Small cells are set to play a leading role in connecting the unconnected, often by putting mobile coverage into the hands of the users themselves. Driven by a diverse set of member-contributed examples, we have grouped rural and remote into seven categories:

Small cells have qualities which makes them particularly well suited to serving:

Rural communities: Coverage for underserved community beyond range of normal service.

Remote industrial: Coverage for community of workers at a site hard to reach from existing infrastructure.

Public safety: Coverage for emergency services & first responders. Disaster recovery/humanitarian: Rapid reinstatement of coverage after

extensive damage to mobile infrastructure, and support for ongoing humanitarian efforts.

Special events: Services for temporary planned gathering. Military: Service for military personnel. Transportation: Services for passengers and operational needs in all

classes of shipping, aircraft and trains.

Each of the Small Cell Forums working groups has analyzed challenges, captured solutions and shared best practices from their perspectives as follows:

Business drivers: Small cells provide cost effective coverage to underserved communities the world over, bringing connectivity to those in need, as well as widening the accessibility of mission critical and high value communications. Small cells leverage existing operator and user investments in infrastructure and devices, bringing high function, low cost benefits of COTS equipment to markets previously limited to bespoke systems with long development lifecycles.

Case histories: presents a diverse set of our members real world success stories deploying small cells in rural and remote scenarios.

Regulatory issues range from small cells moving across national boundaries and the implications on frequency management, lawful intercept and spectrum licensing conditions, to the need to ensure prioritized access for emergency workers.

Backhaul can be just as challenging for remote small cells as other types of RAN. Long-range wireless and new satellite bands have proven to be viable in several of our


case studies. Limited performance, intermittent or even non-existent backhaul can all be accommodated with architectural modifications.

Network architectures are much like those used by enterprise small cells, with a varying degree of core network functionality localized to mitigate backhaul performance and cost issues. Backhaul adaptors can also be added to optimize transport usage over long-range connections.

Virtualization of core network functions is often seen as a solution for scaling up of capacity as networks grow. In rural and remote, it can also enable scaling down of the cost of equipment needed, reducing the barrier to entry for initial deployments. NFV is also an enabler for localizing core network functions to mitigate limited backhaul performance, or even allow standalone operation.

Deployment: Arguably the key strength of small cells is their ease of deployment. In our provided examples, coverage needs to be rapidly achievable by installers with no specialist telecommunication skills. Plug and play and SON technologies developed for other small cell segments are enablers, along with compactness, light weight and low power operation.

Services: Nearly all mobile devices now support APIs and large development communities to create bespoke apps to meet the needs of different industries. In addition, small cells themselves can have APIs to run apps for caching of local content and precise indoor location, to name but two.

Fundamental small cell technologies: The Small Cell Forums focus on the fundamentals continues with our Plugfest programme, and maintenance of our small cell API and SON API, which define and refine open interfaces to foster a healthy and competitive multi-vendor ecosystem.

Further detail on these findings can be found in this overview and in the range of documents illustrated below, all of which are freely downloadable from www.scf.io

Small Cell Forum publications for rural and remote small cells


Contents

1. Introduction .....................................................................1 1.1 Structure of this document ................................................... 1 1.2 Defining rural and remote use cases and their characteristics.... 1 1.3 Value of rural and remote content for different audiences ......... 3 2. Market issues: drivers and challenges, business case

and market status ............................................................4 2.1 Market status ...................................................................... 5 3. Network architecture .......................................................6 4. Backhaul ...........................................................................9 5. Regulatory ...................................................................... 11 6. Deployment .................................................................... 12 7. Services .......................................................................... 13 8. Building an ecosystem around the underlying small cell

technologies ................................................................... 14 8.1 Plugfests for interoperability ............................................... 14 8.2 Small cell API [SCF082] ..................................................... 15 8.3 SON API [SCF083] ............................................................. 16 8.4 Multi technology small cells [SCF073] .................................. 16 9. Conclusions and our roadmap ........................................ 17 References ................................................................................ 18

Tables Table 1-1 Characteristics of the Use Cases ....................................................... 2 Table 3-1 Mapping of Rural and Remote Use cases to SCN Characteristics ............ 7 Figures Figure 2-1 Key small cell market statistics. ........................................................ 5 Figure 3-1 Canonical Architecture for Single-Cell R-SCNs .................................... 6 Figure 3-2 Canonical Architecture for Single-Cell R-SCNs .................................... 6 Figure 4-1 Summary of backhaul challenges ...................................................... 9 Figure 6-1 Deployment framework .................................................................. 12 Figure 8-1 Role of Plugfests in standards and product development and testing ... 14 Figure 8-2 Small cell reference architecture ...................................................... 15

Report title: Rural and remote small cells Issue date: 02 March 2015 Version: 105.5.1 1

1. Introduction

Small cell technologies are coming of age thanks to scaling of deployments in residential, enterprise and now urban markets. These maturing technologies can also be applied to a diverse range of rural and remote use cases that may not otherwise be viable using traditional deployment approaches. Small cells are well suited to deployment in rural villages, remote industrial sites, on transportation, as well as temporary networks for public safety, humanitarian and special events.

Different types of small cells are discussed further in Small cells, whats the big idea? [SCF030]. This document summarizes a range of useful information including terminology, interference management, backhaul, forms of access and the positioning of small cells relative to adjacent technologies including DAS, Wi-Fi and Cloud RAN. It looks at five very different use cases and shows how the momentum behind small cells is growing.

This document provides an overview of all the Small Cell Forums publications covering different aspects of rural and remote small cells. It aims to help readers understand the big picture as well as quickly navigating to the supporting detail.

1.1 Structure of this document

This overview is structured around the different disciplines represented by the Forums working groups. Each group has published papers describing their perspective on the challenges and best practices for deploying rural and remote small cells.

Market: Drivers and barriers, business case and real world success stories

Radio and physical layer: Small cell API, interference coordination, SON, etc.

Interoperability: Reports and roadmap for our Plugfest events, which accelerate maturity of small cell standards and implementations.

Network: Architecture and core networks. Interworking, sync, security, NFV, etc.

Backhaul: Defining requirements and assessing technologies for connecting small cells towards the core network

Deployment: Processes needed to design, build and operate small cell networks

Regulatory: Clarifying national and international policy around the use of small cell technologies

Services: applications that can be run on small cells to add additional value for carriers. Examples include precise indoor location and edge caching.

The sections in this overview outline the documents available and summarise their key takeaways.

1.2 Defining rural and remote use cases and their characteristics

During development what was originally entitled the rural theme, our members provided a wide range of examples of how small cell technologies have been deployed


in diverse conditions and usages, as captured in our case histories [SCF151]. We therefore expanded the title to encompass remote deployments as well. We have grouped examples provided under seven use case headings as shown below. These should be treated as examples to help operators, businesses and people understand the qualities of small cells, and to stimulate ideas for new and innovative applications.

Rural and remote use cases:

Rural community: Coverage for underserved community beyond range of normal service

Remote industrial: Coverage for community of workers at a site hard to reach from existing infrastructure

Public safety: Coverage for emergency services & first responders.

Disaster recovery/humanitarian: Rapid reinstatement of coverage after extensive damage to mobile infrastructure, and support for ongoing humanitarian efforts.

Special event: Services for temporary planned gathering

Military: Service for military personnel

Transportation: Services for passengers and operational needs on all classes of shipping, aircraft and trains

The use cases themselves represent just some of the examples of how small cells can be applied to bring mobile connectivity into areas that would otherwise be cost prohibitive. We show in Table 1-1 a set of characteristics that may always or sometimes apply to the example use cases.

Table 1-1 Characteristics of the use cases

The characteristics refer to the needs of the users, rather than the types of solution that apply. We define them as:

Rural: area outside of towns and cities Remote: Far from existing coverage and mobile infrastructure Moving: On-board coverage moving with users Temporary: Rapidly deployable short-term coverage Dedicated: Limited to specific service or user group

In general, each use case has a defining characteristic that always applies Transportation is always moving, disaster recovery is always temporary, etc. Other


characteristics may only sometimes apply. For example, whilst rural communities are always outside of towns and cities, they are not necessarily remote from existing mobile infrastructure.

1.3 Value of rural and remote content for different audiences

Operators can use the recommendations and case studies to develop their own small cell strategy taking into account specifics of their markets and asset holdings. They can find out about the state of the art of small cell related technologies and understand the roadmap to wide scale commercial deployment. They can benefit from best practices and shared learnings from leading operators who do so to help drive scale and bring down costs for the benefit of all.

Vendors can better understand operator thinking around their motivations to deploy, together with their key challenges and technical requirements. It will help to refine their roadmaps to ensure they will deliver features and performance aligned with industry requirements.

Regulators, investors, municipalities and end users, can all benefit from the collective view of issues that will need to be resolved to facilitate deployment of small cells in diverse environments, bringing the social and economic benefits of enhanced mobile connectivity.

Partner organisations that want to understand how the Small Cell Forum is positioned relative to their activities.


2. Market issues: drivers and challenges, business case and market status

The special characteristics of small cells are a good fit for the requirements of rural and remote environments. But is rolling them out a good fit for an operators business plan? In fact, operators can clearly benefit from connecting the unconnected. Why this is and how such markets can be addressed efficiently and profitably is the main subject of Business drivers for connecting the unconnected via small cells [SCF150], which considers the drivers and opportunities for using small cells to deliver better mobile services in rural and remote environments.

However, as this paper also points out, rural and remote use cases have diverse needs and outcomes. This is clearly indicated in Rural and remote case histories [SCF151], which highlights a compelling range of diverse and innovative real world applications for small cells.

Together, these documents describe and illuminate an impressively diverse range of use cases, all of which can benefit from small cell rollout but each of which has distinct drivers.

Rural communities looks at ways in which small cells can play a key role in connecting underserved communities beyond the range of normal service. There are nearly 1.6 billion such subscribers in both developed and developing countries. In some cases mobile can provide their only access to medical assistance, employment and education. In all cases mobile can improve their economic outlook and basic connectivity. Operators, meanwhile, cannot only reach more people, but strengthen their brand, enhance their reputation for social responsibility and meet regulatory coverage rules. Three case histories appear in this chapter: a rural initiative in the UK, a small cell system that connects previously isolated villages in the developing world, and a system using satellite backhaul in rural and hard-to-serve areas of Latin America.

Remote industrial looks at how small cells can improve coverage for a community of workers at a site hard to reach from existing infrastructure specifically an oilrig off the Gulf of Mexico and the depths of a Swedish mine. Improved productivity, safety and staff retention are obvious customer drivers here while operators can take advantage of higher ARPU, potentially long-term contracts and an important and growing market.

Public safety discusses the role of small cells in providing coverage for emergency services and first responders. This is another growing market, and one that can provide an important source of new business for operators. Its also one to which operators can bring better interoperability, reduced costs and increased functionality through small cells, saving not only time but lives. The case history in this chapter involves communications for incident response vehicles.

Disaster recovery/humanitarian looks at rapid reinstatement of coverage after extensive damage to mobile infrastructure, and support for ongoing humanitarian efforts. Having reliable and secure communications is vital for humanitarian aid and disaster relief workers. It helps them find survivors, provide emergency medical help and request supplies such as medicine, food and clothing. In addition, a robust communications link is necessary for conveying real-time information to local, national or international authorities and aid agencies. Mobile communications, using low power, low cost small cells and optimized satellite backhaul, is reliable, secure and quick to


roll out as the case history discussed here the aftermath of a major typhoon makes clear.

Transportation examines services for passengers and operational needs on transport above ground and offshore. Another vast and potentially rewarding market for operators, this is also one in which passenger expectations of acceptable connectivity are driving the rollout of small cell-supported networks beyond transport hubs, like stations, ports and airports, and on to the modes of transport themselves. This chapter looks at exciting advances for mobile communications that take small cells onto planes, cruise ships and ferries, where they are supported by satellite backhaul.

Special events looks at the growing need for rapid, temporary networks for major events. Again this is a growing market with major opportunities for operators to develop revenue streams from formerly untried sources, although few are as unusual as the one examined in this section: 4G systems that can offer reliable voice, video and telemetry to on-car systems for motorsport.

These studies underline the potential of small cells in helping mobile operators to reach a number of areas that might once have been considered too difficult or uneconomic to serve. That is no longer the case. In fact in SCF 151 an analysis of 215 countries and US states across Europe, Africa, Latin America, the US and South East Asia finds that:

Every country analyzed stands to benefit from small cells. For the same investment as with macrocells 650 million additional people

could potentially benefit from mobile via small cells worldwide.

This 9% increase in coverage equates to approximately $1 trillion increase in GDP worldwide or an estimated operator benefit of $163 billion.

2.1 Market status

The Small Cell Forum provides regular updates on state of market adoption for the different types of small cell technology with Figure 2-4 showing the latest statistics. The latest results can always be downloaded from our website on our Market status report page: [SCF050].

Figure 2-1 Key small cell market statistics. Source: Mobile Experts


3. Network architecture

What network architecture is needed to support the different rural and remote small cell deployment use cases? This is the question tackled by our Rural and remote small cell architectures [SCF153]. Building on the seven identified rural and remote use cases, and their five associated characteristics, this paper analyzes the architectures from the perspective of the four key domains that comprise the rural small cell network; namely small cell access network, local small cell network, small cell core network and macro core network. As a result, it identifies 3 canonical architectures that can be modified to produce architectures for each specific use case.

The simplest canonical architecture for a single small cell is shown in Figure 3-1. The Backhaul Adaptor is optional and is only needed where low bandwidth or high delay transport such as satellite is used.

Figure 3-1 Canonical architecture for single-cell R-SCNs

At the other end of the scale, the most sophisticated canonical architecture includes local small cell concentration and provides local connectivity via various local SCN elements, as shown in Figure 3-2 shows how these different architectures map to our rural and remote scenarios.

Figure 3-2 Canonical architecture for single-cell R-SCNs


Table 3-1 Mapping of rural and remote use cases to SCN characteristics

From a backhaul perspective, rural and remote small cell deployments may well look to make use of satellite-based backhaul between, for example small cells located on a ship or in a rural village and a central satellite operator hub. The satellite link may adversely affect certain backhaul characteristics not normally associated with traditional terrestrial-based backhaul solutions and so particular attention is paid to how such issues can be alleviated through the use of a satellite backhaul adaptation function.

Building on the previous enterprise small cell architectures published in [SCF067] that introduced the concept of local concentration and gateways to access local (enterprise) services, the rural and remote small cell architectures show how such capability can be leveraged for supporting local services. However, going one step further, the architecture enables support for complete distribution of the small cell gateways and management, as well as the conventional macro core elements to enable the realization of a stand-alone system that can be deployed in total isolation of the macro network. These concepts are then applied to three key transportation use cases, covering aircraft deployment, ship based small cells as well as train based small cell architectures.

[SCF153] closes with a review of the standardization activities that are related to rural and remote small cell network architectures. In particular existing standards on mobile relays and ongoing activities such as isolated E-UTRAN and enhanced infrastructure-based communication between devices (eICBD) are relevant to the deployment to small cells in specific rural and remote scenarios.

Many of the deployment examples demonstrated in our case histories document [SCF151] require much smaller scale networks than typical of residential, enterprise and urban deployments. The cost of a dedicated small cell network may be perceived a barrier to entry for some rural and remote applications but virtualization has a role to play here, enabling core network functions to be scaled down as well as up: Small cell core network virtualization [SCF154] examines the industry transition of network function virtualization (NFV) that is impacting all service provider segments. The document explores virtualization of small cell core network functions necessary to support different small cell markets. Functions considered include core small cell gateways, security gateways and small cell management systems, enterprise market segment specific functions including small cell concentrators and gateways as well as virtualization of the more conventional 3GPP core network functions for certain rural and remote use cases. The approach is to translate concepts pioneered by ETSI NFV and apply those to the small cell core network domain.


Importantly, being able to apply virtualization techniques to the small cell core network functions will enable the barriers to entry for these small cell use cases to be diminished not just for rural and remote, but more broadly across the wider set of small cell market segments. Key considerations related to the support for scalable IPSec within an NFV small cell environment together with the impact of NFV on the distribution of phase and frequency synchronization are addressed.

The key takeaways from our core network virtualization paper [SCF154] are:

vendors and operators can re-use broader NFV approaches that are beginning to impact the implementation of 3GPP core networks to support small cell core networking capabilities, and

by virtualizing small cell core network functions, barriers to entry for small cell deployment can be reduced.


4. Backhaul

Small cells reduce the cost of ownership by being cheaper, easier and faster to deploy than other types of RAN. However the opportunities for reducing the cost of backhaul connectivity are more limited especially since operators are clear that the quality and performance of the resulting services cannot be compromised [1].

A range of new backhaul technologies have been developed to tackle these challenges, which, when combined can meet all operators needs, as shown in Backhaul requirements and solutions [SCF049]. Whilst many of these target the particular challenges of the urban scenario (detailed in [SCF095]), developments in satellite and non line of sight technologies are also described which apply to our rural and remote scenarios.

In this overview we have identified a number of applications to which small cells are particularly well suited. Due to their cost, size, low time to install and portability, other types of RAN have not covered many of these. In many cases though, backhaul is still one of the main hurdles. Figure 4-1 summarizes different backhaul challenges presented by the conditions that can be experienced, and identifies the potential solutions in each case. These range from the technicalities of connecting to a moving small cell site on a train or plane, to the economics of connecting a remote community with only a small potential revenue for the operator. We note that multiple characteristics and challenges may apply in some scenarios: ships and trains are always moving, and sometimes remote as well.

Figure 4-1 Summary of backhaul challenges

Backhaul for rural and remote small cells [SCF155] helps operators, backhaul and service providers to understand the particular needs of rural and remote small cells


from a backhaul perspective. It summarizes key aspects that must be considered when designing and deploying the transport network, and points to sources of further information.

Key findings are:

Remote deployments by definition are far from existing network infrastructure and thus are potentially expensive to backhaul with terrestrial links. Satellite becomes cost effective here and has proven suitability for backhaul, illustrated in many of our case histories in [SCF151]

Rural deployments are not necessarily remote, and may be in the next valley from a larger town with connectivity. Shorter-range backhaul and copper connectivity can be used here.

Small cells deployed on ships, planes and trains require backhaul that can connect to a moving cell site. Non LOS and satellite backhaul have been demonstrated for these applications in our case histories paper [SCF151]

Temporary deployments typically require rapidly deployable backhaul. Low power consumption is also desired to make a wider range of supply technologies viable.

Backhaul to remote areas is likely to have limited performance:

As little as 50kbps capacity is sufficient to provide a basic 2G voice and SMS service.

Data service bandwidth will likely be limited by the willingness to pay for backhaul bandwidth. Compression techniques and avoiding the need for IPsec overheads can bring significant value here.

Latency of around 300ms one way is tolerable for voice, but can limit TCP connection bandwidth if acceleration technologies are not implemented. Localized call switching and content access avoids backhaul limitations where applicable.

The backhaul adaptor function described in the network architectures section and [SCF153] can help mitigate impact of lower transport performance.

The Metro Ethernet Forum (MEF) has implementation agreements that are also applicable in rural areas. Standard SLAs help operators work with a range of different last mile providers, and multi-CEN (carrier Ethernet networks) provide a framework for defining end-to-end performance over multiple connections from different providers.

Networks can be deployed with intermittent or even no backhaul connectivity by localizing core functionality. These isolated networks can still provide local call routing and access to local content, bringing the benefits of COTS telecoms to remote and private networks.

Backhaul solutions are available which meet the challenges of deploying small cells cost effectively in rural and remote use cases. Different solutions are described which address the challenges of rural and remote deployments in order to deliver cellular voice and data to COTS devices in these applications.


5. Regulatory

Regulation is an ongoing concern and one that will clearly differ from one use case to another. Operators therefore want to know more about the regulatory requirements they must consider for the various deployment categories of small cells and what regulators are doing to help such deployments. In addition operators have asked the Small Cell Forum about the regulatory impact on sharing sites, spectrum and backhaul, E911 device location, and lawful intercept in the context of small cells.

Given the numerous administrations involved across dozens of countries, these issues are constantly developing and changing. The baseline document for discussion of this, however, is our paper on Regulatory aspects of small cells [SCF076]. This paper covers aspects relating to all types of small cells, residential, enterprise, urban and rural and remote.

Deployment of small cells in our rural and remote scenarios can introduce new regulatory issues. Particular emphasis is focused on the transportation use cases that involve small cells being deployed on ships, international trains and aircraft:

From a shipping perspective, regulatory frameworks have been developed in many regions in order to ensure that the use of wireless access points on ships does not cause interference into land-based licensed networks using the same spectrum.

From a rail perspective, the future use of small cells on international train services may require harmonized regulatory measures to be put in place to enable successful frequency coordination and usage when travelling across country borders. Furthermore, in some countries there may also be a need, for adjustments to the power thresholds that trigger a requirement to notify the regulator of the geo-location of the transmitter. Finally, there will be a need to take into account adjacent band compatibility with GSM-R, when planning small cell operations on trains in the 900 MHz bands in Europe.

From an aviation perspective, the European regulators have developed a harmonized regulatory framework to facilitate operation of on-board GSM, UMTS and LTE small cells on European flights were traversing airspace across national borders. Issues related to possible interference towards ground based systems from the in-flight small cell installation are covered.

For public safety and disaster recovery situations, small cells may be configured to provide dedicated services to only emergency workers. Alternatively public access small cells may be deployed in situations where they need to support authorized national security and emergency preparedness users. The services supported will be expected to support those same priority and pre-emption capabilities available over a macro network. This ensures authorized emergency users have priority access to the small cell network, even in times of heavy network congestion.

Finally, several national and international regulatory bodies have taken specific steps to clarify issues of policy and regulation relating to small cells and some have revised their regulatory requirements to facilitate their deployment. Several examples are described in our regulatory white paper. Most bodies take into account the positive role of small cells in helping to guarantee mobile services and the control that operators can exert over small cells as part of their existing network. The Small Cell Forum is maintaining a register of applicable regulations in locations of interest to its members and helping to spread examples of regulatory best practice.


6. Deployment

Deployment issues for rural and remote small cells [SCF156] considers the planning, designing, building and maintaining of the small cell network in our rural and remote scenarios. This, until recently, would have normally been undertaken by a mobile network operator. The document explores the major differences between the processes for each use case and looks at ways in which small cell deployments can be efficiently completed, potentially reducing costs, by the operator or a third party company/vendor. The exact processes for deployment of each use case can vary significantly between one another. The Deployment issues for rural and remote small cells suggests a set of procedures grouped according to plan & design, build, and operate phases, as shown in Figure 6-1.

Figure 6-1 Deployment framework

Commercial models: The seven rural and remote use cases can have a number of different commercial models driven by four different types of organizations. Communities and end organizations are like to play a key role in rural and remote deployments.

Plan and design: Access to backhaul, power and local resources would typically be key factors to consider for certain remote sites. For moving environments such as trains or planes, factors such as interference management and vibration may require particular attention. However despite the wide variability of rural and remote use cases, small cell networks are generally well suited for these environments given their relative compactness and design simplicity.

Installation, commission and acceptance: Pre-staged equipment, deployment video tutorials, remote integration and support will make the remote deployment process achievable by local personnel. Deployments in ships and aircrafts will be certified to a certain degree and performed by local crew during maintenance windows.

Operation: The operation and maintenance of rural and remote small cells will vary due to diversity of use cases. Different types of organizations such as MNO, neutral host, a specific community or an end organization entity could be responsible for operation and maintenance tasks. As such, it would be critical to standardize as much as possible. Standardized small cell kits for various use cases will simplify the operation and maintenance as well as reduce the sophistication level for the personnel maintaining these systems. Basic certification levels should be created for the field force to ensure a certain minimum level of competence in the field.


7. Services

Rural and remote small cells application services [SCF157] defines a number of useful rural and remote services that can be implemented by mobile operators. There are several existing examples of small cells delivering the connected farm, enabling connectivity for remote mining camps, disaster recovery, telemetry and data collection for electric service, gas, oil, water and utility grids and delivering mobile services on planes and ships.

Location-based services and presence zones with small cell based location technologies are a key enabler for precision indoor location (PIL) based applications, applicable to rural and remote deployments.

IP-PBX integration can be used by enterprises to leverage small cells and mobility, in particular through integration with their existing fixed assets such as private branch exchanges (PBXs) and local area networks (LAN).

Internet of Things is a growing M2M market evolving around the need to monitor the location and state of various assets.

Caching at the small cells can provide the twin benefits of reducing the loading and optimizing users quality of experience QoE that may further reduce small cell backhaul demands and related costs.

The use of small cells for rural and remote applications are extremely valuable and there are endless possibilities for new services and applications that are useful for subscribers and allow mobile operators to provide cost effective solutions to areas that may not have previously had sufficient coverage or capacity for mobile communications.


8. Building an ecosystem around the underlying small cell technologies

The success of the small cell ecosystem relies on the forums continued focus on the fundamental technologies and activities that foster a healthy ecosystem. The Small Cell Forum has defined open APIs for the small cell reference architecture and SON to encourage competition though exchange of parts between multiple vendors. We also maintain a programme of interoperability testing to ensure these and other small cell standards are clear and unambiguous so that the implementations from multiple vendors all work together. Further details on the range of ecosystem building activities undertaken by the forum can be found in our Release structure and roadmap [SCF100]

8.1 Plugfests for interoperability

A strong small cell ecosystem requires that operators have a wide choice of interoperable equipment from a range of suppliers from which to build their heterogeneous networks. Manufacturers also benefit from the economies of scale that a successful ecosystem brings.

Achieving a state of ecosystem interoperability requires both good quality standards and equipment that conforms to them. Our Value of small cell forum Plugfests [SCF085] paper describes the role of interoperability testing:

Figure 8-1 Role of Plugfests in standards and product development and testing

Equipment from different manufacturers is connected and operated in a range of real life scenarios. This tests both the suppliers implementation of the standards, as well as the quality of the standards themselves.

Failed tests drive debugging of implementations, as well as resolution of ambiguities, gaps and incompatible options in standards.

Successful testing demonstrates mature and interoperable standards and equipment.

Conformance testing later checks that products correctly implement the requirements of the interoperable standard.

The Small Cell Forum, ETSI and NGMN Alliance have been working together since 2010 to conduct Plugfests to accelerate alignment of small cell network technologies. At the time of writing, four events have tested interoperability of 3G and LTE small


cells networks, and a fifth set for June 2014 will include testing of multi-vendor SON functionality in heterogeneous networks.

8.2 Small cell API [SCF082]

The small cell application platform interface1 (SC-API) is both a cornerstone of the low cost small cells ecosystem, as well a candidate for their future evolution towards virtualisation. SC-API is the product of an ongoing initiative to encourage competition and innovation between suppliers of platform hardware, platform software and application software. It does this by providing a common API around which suppliers of each component can compete. In doing this, we imitate a long and distinguished engineering tradition of providing an interchangeability of parts to ensure that the systems vendors can take advantage of the latest innovations in silicon and software with the minimum of entry barrier, and the least amount of custom re-engineering.

LTE SC-API [SCF082] is regularly updated and in Small Cell Forum Release Five is 3GPP Release 10 compliant. The SC-API is defined via a reference architecture shown below, which is generic to 3G or 4G small cells.

Figure 8-2 Small cell reference architecture

P1 the security coprocessor interface P2 the service discovery interface P3 the GPS interface P4 the network listen results interface P5 the PHY mode control interface P6 the ciphering coprocessor interface P7 the main data path interface M1 the scheduler interface

LTE-SC-API defines the P5 and P7 interfaces. Our current study of virtualization considers splitting of the small cell along different parts of the PHY and MAC, and SC-

1 Formerly known as the Femtocell API (FAPI)


API is a candidate. The Small Cell Forums proposals will be the subject of a future release.

8.3 SON API [SCF083]

The self-organising network application platform interface SON API [SCF083] defines and enabler of SON functionalities for small cells, based on high-level requirements that are independent of the particular SON architecture. The document explains how the SON API is based on high-level procedures for exchange of information between cSON and dSON, which are grouped into global procedures (general character) and function specific procedures (for a particular SON function). For each procedure, the detailed definition of exchanged information is an integral part of the SON API and covers in general parameters, performance statistics and notifications. The work also provides useful guidelines for SON API adoption and integration it into existing management interfaces for small cells.

8.4 Multi technology small cells [SCF073]

Examines the co-existence of 3G and 4G technologies in small cells. It explores possible technology synergies that could serve as integrated solutions for future multi-technology small cell deployments. This includes different architectures and their pros and cons in terms of optimization of product integration and signaling, system robustness, security, flexibility and scalability for future upgrade, and networks saving in CAPEX and OPEX. Trade-offs between multi-RAT RRM architecture, performance, strategies and signaling overhead are required to find the optimum multi-RAT RRM solution. An integrated multi-RAT radio resource management solution is proposed. Benefits in terms of load balancing, interference mitigation, or possible reduction in signaling overhead, etc., shall be evaluated based on individual operators deployment use cases and offered services.


9. Conclusions and our roadmap

Rural and remote scenarios exemplify the diverse range applications in which operators can use small cells to deliver high value mobile voice and data services to people and businesses. Their plug and play and self-organizing nature makes them suitable for rapid deployment by the end users themselves. Their use of standardized air interfaces leverages years of industry investment in mobile infrastructure and cost efficiencies possible using commercial-off-the-shelf devices. At the same, services and applications can easily be customized to meet end users needs, drawing on the established developer community for device based apps as well as custom apps implemented on small cells themselves.

The publication of our rural and remote theme completes a full set of market segments for small cells: Home, enterprise, urban and now rural and remote. However, our work is not done until there are large-scale deployments of small cells across the globe. Looking ahead, the Small Cell Forum will continue to drive adoption by identifying and resolving barriers, sharing best practice success stories from the market leaders, and fostering a healthy ecosystem. Our Release structure and roadmap [SCF100] describes our ongoing thematic updates and additions to our release content.

It is widely accepted now that large-scale deployment of small cells is a certainty - the only remaining question then, is when will you begin to benefit from them?


References

1 Small Cell Backhaul Requirements, NGMN Alliance, Jun 2012, http://goo.gl/eHHtx

Version ControlScopeExecutive summaryContents1. Introduction1.1 Structure of this document1.2 Defining rural and remote use cases and their characteristics1.3 Value of rural and remote content for different audiences

2. Market issues: drivers and challenges, business case and market status2.1 Market status

3. Network architecture4. Backhaul5. Regulatory6. Deployment7. Services8. Building an ecosystem around the underlying small cell technologies8.1 Plugfests for interoperability8.2 Small cell API [SCF082]8.3 SON API [SCF083]8.4 Multi technology small cells [SCF073]

9. Conclusions and our roadmapReferences

Documents

105 Rural-Remote Overview