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Challenges and Best Practices in the Deployment and Management of IPTV Networks © 2007 EMC Corporation

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Challenges and Best Practices in the Deployment and Management of IPTV Networks

EMC Proven® Professional Knowledge Sharing May, 2007

Paul Brant Advisory Technology Consultant

EMC Corporation [email protected]


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Abstract Reliability and quality of service are the greatest challenges faced by Internet Protocol Television (IPTV) operators as they deploy IPTV and other broadband services. These complex services must be extremely resilient. If consumers experience less than optimal levels of service, both the services and their providers will not remain viable.

Integrating video-over-IP equipment into existing metro and access networks is a difficult challenge, but how can service providers be sure those networks are capable of delivering quality service while growing from thousands to millions of customers? We will look at the video-stream and integrated triple-play/multicast video solutions available and examine how they work.

Video service delivery, for example, places high bandwidth demands on its network and related applications as the provider integrates storage, delivery and access to the consumer. The scalability requirements are also enormous and can include thousands of servers with back-end storage in the petabyte range. This challenges any deployed solution.

Networks rely on multiple layered protocols such as MPLS, Ethernet, IP and Multicast. Since the layers are independent, a problem in a lower protocol can be masked and spread to the other protocols. This type of lower level protocol disruption can be easily hidden and difficult to diagnose. In networks of this size, diagnoses must be timely, issues easy to isolate and the solution must be accurate.

The EMC Smarts® solution, including IPTV support, helps service providers create a high availability and performance environment. Smarts� powerful modeling, cross-domain correlation, analysis and scaleable and distributed architecture make it capable of supporting and managing large complex environments and capable of isolating problems with a high degree of accuracy.

This paper will discuss the unique management challenges posed by next generation networks (NGN), how the EMC Smarts architecture is uniquely suited to address these challenges, and will present Best Practices.

Disclaimer: The views, processes or methodologies published in this article are those of the author(s). They do not necessarily reflect EMC Corporation�s views, processes or methodologies.


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Table of Contents Challenges and Best Practices in the Deployment and Management of IPTV Networks ..............................................................................................................1

Abstract ........................................................................................................................................2 Table of Contents .........................................................................................................................3

Introduction .........................................................................................................4 What are Next Generation Networks?..........................................................................................4 What is IPTV?...............................................................................................................................4

Fundamentals of IPTV Networks........................................................................4 IPTV and the Digital Home...........................................................................................................5 IP Broadcast Challenges..............................................................................................................8

Synchronization ........................................................................................................................8 Broadcast Addressing...............................................................................................................9

Interconnecting the Broadcast LAN to the WAN ........................................................................10 Endless Channels, Multiple Delivery Options ............................................................................12 Service Providers - New Needs and Requirements...................................................................12 IP-TV Management and Monitoring - Network Architecture Challenges ...................................17

IPTV NGN Management Challenges and Best Practices ...............................19 Best Practices in Root Cause Analysis ......................................................................................21

Rules-based Correlation Limitations and Challenges.............................................................22 Best Practices � Rules-based Correlation using CCT............................................................22 Best Practices - Reduction of Downstream Suppression .......................................................23

Best Practices - Having a Robust Information Model.................................................................24 Best Practices - Aligning NGN and IP-TV Technology to Business Level Requirements .........25

The ICIM Common Information Model....................................................................................26 Analysis...................................................................................................................................26 Automation..............................................................................................................................26

Best Practices in Scalability .......................................................................................................27 Best Practices in Open Integration.............................................................................................29 Best Practices in MPLS Management........................................................................................30 Best Practice in Optical Network Management..........................................................................31

Conclusion.........................................................................................................31 Appendix A � Abbreviations ............................................................................33 Appendix B � References .................................................................................35


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Introduction

What are Next Generation Networks? Next-generation networks seamlessly blend the public switched telephone network (PSTN) and the public switched data network (PSDN), creating a single multi-service network. Typically, networks are large, centralized, proprietary switch infrastructures. Next-generation architectures push central-office (CO) functionality to the edge of the network. The outcome is a distributed network infrastructure that leverages new, open technologies to reduce the cost of market entry, increase flexibility and reliability, advance management with fault isolation, and accommodate both circuit-switched voice and packet-switched data.

What is IPTV? During the last few years the growth of satellite service, digital cable, and expanding deployment of HDTV have all changed the video content landscape. Now, a more advanced and complex delivery paradigm threatens to have major impacts. The Internet Protocol Television (IPTV) has arrived, supported by the major telecommunications providers. IPTV is ready to offer more interactivity and options, and to compete in the business of selling TV and entertainment. IPTV describes a system capable of receiving and displaying a video stream encoded as a series of Internet Protocol packets. If you've ever watched video on your computer, you've used an IPTV system. When most people discuss IPTV, though, they're talking about watching traditional channels on your television, where demands such as a consistent, high-definition, latency picture are expected. The telecommunications providers are entering this market and more will follow. Once known only as phone service providers that offered POTS (Plain Old Telephone Service), the telephone companies (telcos) now want to offer the "triple play" that includes voice, data, and video. The cable and telecommunications providers are the most aggressive competitors. They are investing in new fiber rollouts and backend. They recognize that the stakes are far higher than just television service. Those who can offer the triple-play want to become your sole communications link, giving you both �Quality of Service� and high availability. IPTV is a major part of the strategy to keep the network up and running, and minimize down-time. The key goals are availability and reliability.

Fundamentals of IPTV Networks

This section describes how IPTV works and the network and application infrastructures that support it.

Wire-line carriers realize that in order to support IPTV services they can no longer incrementally enhance or "optimize" existing network elements. Unlike high-speed Internet access, IPTV must compete with a long-entrenched incumbent: cable TV. To compete successfully, carriers will have to overhaul their existing network architectures to enable greater capacity, flexibility and manageability. Unlike their cable competitors, whose network equipment investments suggest gradual optimization, carriers who will be supporting NGN (Next Generation Networks) have a unique opportunity to leapfrog currently available offerings by delivering a radically improved TV viewing experience to subscribers. In addition, Time-shift TV and Video on Demand (VOD) also impact network design.


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IPTV and the Digital Home IPTV is a critical element of the digital home, an evolving term describing the trend toward home subscriber environments, including inter-networked elements that enable seamless user experiences regardless of content origin for TV, music, phone, and high-speed Internet. Enabling these new services requires the ability to deliver sufficient network capacity. In order for carriers to predict bandwidth requirements, and the impact of this prediction on equipment selection and deployment, it is useful to have a starting point for simultaneous service delivery to the digital home. Initially, it is safe to assume that this would include two Standard Definition (SD) and one High Definition (HD) TV streams, three Voice over IP (VoIP) phones, and streaming digital audio/music. The Diagrams shown in �Figure 1 - Data Rate Graph� and �Figure 2 - Video Data Rate as a function of application� illustrate the bandwidth required for typical applications, transport and image resolution types. For example, raw HDTV requires 1.5 Gbits/s bandwidth. Video conferencing requires 0.4 Mbits/s. This rounds out the high and low end bandwidth requirements and all other applications needs in between. The Video/Audio provider performs several tasks, including the production and transportation of the broadcast material.

Figure 1 - Data Rate Graph

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Figure 2 - Video Data Rate as a function of application In Digital TV, the underlying transport protocol is MPEG-2 transport Protocol, which is a part of the MPEG-2 standard. MPEG-2, or Moving Picture Expert Group 2, is a standard body that provides efficient ways to code and to transport digital television 1. Thanks to this standard, a video encoder can take the video component of an uncompressed digitized television stream whose bit rate is usually around 210 to 216 Mbits/s and compress it to around 12 Mbit /s for a HD quality and around 4 Mbit/s for an SD quality. The information in Figure 1 - Data Rate Graph and Figure 2 - Video Data Rate as a function of application shows additional video applications and the associated data bandwidth requirements. An audio coder can compress the audio part to a few hundred Kbit/s. These elementary streams contain bits of audio and video for each television channel and are then cut into transport packets that are passed to a multiplexer that combines several channels and adds additional service information to ease the decoding process at the set-top box level. These transport packets are the glue of the digital television transport layer. All of the MPEG-2 equipment in the broadcast station communicates programming in the form of a series of MPEG-2 transport packets. Such a series is called an MPEG-2 transport stream, or MPEG-2 TS. See Figure 3 - MPEG-2 System, shown on the following page.

1 ISO/IEC 13818-1 : Information Technology- Generic coding of moving pictures and associated audio information- Part 1 : Systems- International Standard (IS)

Application Data Rate (Mbits/s)Video Conference 0.4Video in a Window 1.5

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Figure 3 - MPEG-2 System

In the multiplexer, each transport packet contains a part of an elementary stream. In order for the set-top box to reconstruct an elementary stream from its packets properly, a mechanism that flags each packet has been derived by MPEG-2. Each packet is divided into a payload that contains a chunk of the elementary stream, and a header containing useful information for transportation and decoding.

The Packet Identifier (PID) can be found in the packet header. The PID allows an elementary stream to be associated with its packets. Therefore, a set-top box trying to decode the video looks at the incoming transport stream and keeps only the PID associated with this video, extracts the portion of the video elementary stream from the packet payload, and passes the resulting stream to a video chip that reconstructs the original content.

A set of tables lists all the logical links between PIDs and elementary streams: the Program Association Table (PAT) and the Program Map Table (PMT). The PAT gives a count of each channel within the transport stream whereas the PMT provides a link between its corresponding video and audio components and their associated PIDs for each channel.

Once the television signal has been formatted into an MPEG-2 transport stream, it may then be broadcast on five different media; satellite, cable, terrestrial, LAN (Local Area Network) or WAN. Today, contributing terrestrial networks are primarily satellite and cable networks. However, local area networks are also being considered to distribute MPEG-2 video and audio content.

The satellite network is a commonly used medium for national broadcasters and is used to send programming from a national center to regional affiliates. On one hand, the satellite is a highly secure and reliable medium that perfectly matches the broadcast model (one to many). On the other hand, the high cost of a satellite transponder is fixed. The transponder bandwidth is also limited to around 40 Mb/s, which allows the transmission of approximately 8 television services, but not the additional load of regional programming.

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In a cable television system, the television signal may arrive to the cable head-end by different means, including satellite, UHF, VHF and Microwaves. All these signals are combined to form a full complement to be sent to a given neighborhood. Here, optical fiber is the support of choice 2. With advanced compression standards (H.264), this digital home scenario suggests a minimum bandwidth requirement of 15 megabytes. This is a conservative estimate based on available technology, but will surely increase as HD content becomes ubiquitous and HD-capable displays become increasingly commoditized. This is critical for carriers to bear in mind because three simultaneous HD streams alone require 24 megabytes, without considering the requirements for upcoming applications such as video telephony and personal broadcast. This could drive the bandwidth requirements for the digital home to 50Mbps and above, which will have a number of implications for carriers as they select appropriate access technology solutions.

IP Broadcast Challenges It is possible to carry broadcast services across IP local area networks. However, there are two main challenges, Synchronization and Broadcast Addressing.

Synchronization The first challenge is that a television stream has audio and video components that are highly synchronized. Therefore, it is critical that this synchronization be maintained throughout the local area network. In the case of a Gigabit Ethernet network that is centralized over a single building, there is enough capacity for bandwidth, jitter and delay, to put the MPEG-2 transport packets directly into IP data grams. The Digital Video Broadcasting (DVB) community defines two ways of encapsulating MPEG-2 traffic over IP. One is to put the MPEG-2 packets directly over UDP/IP data grams, and the other is to put the MPEG-2 packets first into RTP and then into UDP/IP data grams3. RTP is the Internet-standard protocol for the transport of real-time data, including audio and video. It can be used for media-on-demand as well as for interactive services such as Internet telephony. RTP consists of a data and a control part. The latter is called RTCP. The data part of RTP is a thin protocol providing support for applications with real-time properties such as continuous media (e.g., audio and video). It includes timing reconstruction, loss detection, security and content identification. RTCP provides support for real-time group conferencing of any size within an internet. This support includes source identification and support for gateways like audio and video bridges as well as multicast-to-unicast translators.

RTP offers quality-of-service feedback from receivers to the multicast group as well as support for the synchronization of different media streams. While UDP/IP is its initial target-networking environment, efforts have been made to make RTP transport-independent so that it could be used over other protocols.

2 Donald Raskin & Dean Stoneback, edi. Prentice Hall, Broadband Return Systems for Hybrid Fiber/Coax Cable TV Networks, 1999 3 Transport of DVB Services over IP-based Networks, draft of the DVB-IPI ad-hoc group, ref IPI2001 016, October 2001


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The MPEG-2 transport stream is split into as many single program transport streams (SPTS) as there are services. Each service is then encapsulated into UDP/IP packets that have the same IP destination address. A variant is to put the whole TS into a single IP stream, which is useful for IP contribution networks. The DVB community has looked at the RTP/RTCP suites that come from the Internet streaming community. Unlike the broadcasters that look at high quality broadcast material and broadband networks, the internet streaming community addresses the issue of sending low bit rate, low quality material over networks of unknown reliability. One can use RTP for this purpose since it is a protocol written for multimedia streams over IP networks: it can simultaneously handle multiple flows, like audio and video, and provides tools to remove time jitter at the receiver level as well as recover time relationship between multimedia streams. RTP packets have a time stamp in the header that can be used to remove jitter. An RTP companion, RTCP is used to monitor RTP sessions. However, there is a debate about whether RTP is that useful for MPEG-2 transport streams that carry video should they be single program or multiple program transport streams. An MPEG-2 TS may have enough timing information (PCR mechanism) for equipment to perform jitter recovery in case it is needed, this for a SPTS or a MPTS.

Broadcast Addressing The second challenge is that television is by definition a broadcast application, whereas TCP/IP and UDP/IP are essentially unicast (data grams targeted to a single receiver). Even if IP addressing reserves a space for multicast (data grams targeted to a group of receivers) and for broadcast (data grams to all receivers), some new tools, namely the multicast protocols, have been derived to increase the efficiency of this type of application over the Internet. Multicast has been introduced to counter problems experienced with the introduction of broadcast applications on the IP networks. When using a unicast address, a content server that wants to send the same multimedia file to hundreds of users has to duplicate it into as many copies, resulting in loss of bandwidth. A Multicast-enabled network would allow the same server to send the file only once to hundreds of users. Multicast defines a group that is a receiving content at multicast addresses at the same time. It allows a user to join a group and to view multimedia content. A user can also leave a group, and if no members remain, the multicast group can be torn down4. These different operations are defined in a standard called IGMP version 25. Multicast is therefore a useful Internet tool to prevent network clogging. It is also a powerful tool to optimize bandwidth management.

4 Pierre Clément and Eric Gourmelen, Internet and Television Convergence, IP and MPEG-2 Implementation issues, NAB 2000 Proceedings 5 B. Fenner, Internet Group Management Protocol, Version 2 , RF 2236, November 1997

Challenges and Best Practice© 2007 EMC Corporation

Interconnecting the Broadcast LAN to the WAN Once the MPEG-2 transport stream is carried onto the IP local area network, the broadcast traffic has to be put onto the wide area network. Bearing in mind that the IP broadband network is used as a contribution network by the broadcaster, the challenge is to send the broadcast IP signal to well known affiliates. One option is to use an additional Input/output Module within the Gigabit Ethernet switcher that encapsulates the IP traffic into ATM and then, onto SONET/SDH 6. Illustration:

6 Ayan Banerjee & All, GeneraEnhancements, IEEE Commu

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lized Multiprotocol Label Switching: An overview of Routing and Management nications Magazine, January 2001

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Asynchronous Transfer Mode (ATM) adds a level of traffic engineering. ATM is a connected point-to-point technology that guarantees quality of service. It has gained wide acceptance in the telecommunications backbone industry. However, it does not perform optimally for a point to multipoint distribution model, in the same manner as SONET/SDH. In fact, the broadcast IP stream may be duplicated into as many streams as there are regional affiliates, thereby increasing broadcaster cost. To prevent this, one should opt for a Telco or an ISP that offers multicast capabilities. An optimization would include directly encapsulating the IP traffic onto SONET/SDH, therefore eliminating the extra overhead due to the IP over ATM encapsulation (15% to 3% on average). This method is called Packet over Sonnet (PoS). PoS has become increasingly popular and is supported by many Telco and Internet service providers. Mapping the Ethernet frames over fiber is another option. If commonly used on a LAN, this solution has not been scaled on distances greater than 5 km until recently. This is due, in part, to the lack of commercially available extended-length Gigabit Ethernet links. This trend will begin to change now that there are extenders on the market that can increase the link to about 120 km without optical amplification. When coupled with inline optical amplifiers appropriately spaced along the link, the link can be increased into the 1000 km range7. Ethernet therefore becomes an interesting and economical alternative to ATM/SONET or SONET/SDH WAN. Implementation costs of Gigabit Ethernet based WANs are routinely less than 25% of costs for a comparable POS/SONET/SDH or ATM/SONET network8. Moreover, Gigabit Ethernet in the WAN transparently interconnects Gigabit Ethernet LAN with Gigabit Ethernet WAN. And lastly, multicast distribution is far more natural on Ethernet than on point-to-point mechanisms such as ATM or SONET/SDH. The broadcaster must choose between the SONET/SDH and the Gigabit Ethernet technologies. Reliability is the key differentiator. The SONET/SDH optical network is very reliable. An analysis9 from Casner & All shows that IP backbones perform very well and can support delay-critical services. Measurements performed on a fiber link (IPoATMoSONET) between San Francisco and Washington D.C. during a four-month evaluation period show a 99.99% availability and a jitter lower than 1 ms for packet sent. As shown in another study, availability of the fiber link can be further increased with a redundancy at up to 99.9997 %10. Gigabit Ethernet optical WAN, based upon the same physical link, demonstrates the same level of performance. The link protection and restoration capabilities offered by SONET/SDH layer can be achieved with Gigabit Ethernet by combining redundant hot �stand by� links and link aggregation techniques.

7 David G. Conningham & William G. Lane, edi. Macmillan Technical Publishing U.S.A, Gigabit Ethernet Networking, 1999, p 477 8 David G. Conningham & William G. Lane, edi. Macmillan Technical Publishing U.S.A, Gigabit Ethernet Networking, 1999, p 480 9 Stepen Casner & All, A Fine-grained view of high performance networking, input to DVB-IPI, ref DVB-IPI2001-70 10 Donald Raskin & Dean Stoneback, edi. Prentice Hall, Broadband Return Systems for Hybrid Fiber/Coax Cable TV Networks, 1999, p107


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Endless Channels, Multiple Delivery Options Service providers have many options for delivering high bandwidth to the digital home. DSL technologies, at least for the Telco�s, have grown in recent years and analysts predict this trend will continue. Digital Subscriber Line Access Multiplexer (DSLAM) platforms are required to accommodate current bandwidth requirements while providing a path for future growth. This means providing a backplane sufficient to support both today's and tomorrow's highest speed DSL variants. Other options include ADSL2+, which is available today, with up to 26 megabytes downstream and 3-6 megabytes upstream; and VDSL2, with up to 100 megabytes downstream and 50-100 megabytes upstream. Carriers must consider next-generation DSL standards when selecting DSLAM platforms. Management is another important consideration in the landscape of operational efficiency. Passive Optical Network (PON) technology provides a compelling complement to DSL for Fiber-to-the-Node (FTTN) applications, and/or a compelling alternative, in the case of Fiber-to-the-Home/Business (FTTH/FTTB) applications. An ideal solution occurs when fiber is available in the access network, and PON technology's symmetrical nature anticipates new types of interactive, bandwidth-intensive subscriber applications like video telephony. PONs combine the high capacity of fiber with the scalability of point-to-multipoint network topologies. Two PON variants play an important role in access networks serving digital homes: Gigabit Ethernet PON (GEPON) which is available today and ATM-based Gigabit PON (GPON) which will be available in the future. The currently available GEPON variant enables a single Gigabit Ethernet uplink to be split between 32 subscribers, affording 30 megabytes of symmetrical bandwidth to each connected digital home.

Service Providers - New Needs and Requirements The set-top box, which seemed to be obsolete in the cable world, is re-appearing for IPTV systems. The IPTV set-top box will connect to the home DSL line or whatever �Last Mile� technology is available and responsible for reassembling the packets into a coherent video stream and then decoding the contents. Windows or Apple computers could do the same job, but the �always-on PC� is still a future solution. The PC is still, for the most part, not connected. So, it seems that the STB will make a comeback. Where will the box pull its picture from? To answer that question, let's start at the source. Most video enters the system at the telco's national head-end, where network feeds are pulled from satellites and encoded if necessary. The encoding protocol is often MPEG-2, as discussed previously, though H.264 and Windows Media are also options. The video stream is broken up into IP packets and dumped into the telco's core network, which is a massive IP network that handles all sorts of other traffic (data, voice, etc.) in addition to video. Owning the entire network is a major advantage. Since quality of service (QoS) tools can prioritize video traffic to prevent signal delay or fragmentation, there is hope that similar performance can be achieved relative to what is considered commonplace in the existing TV world. Without control, management, and the ability to isolate problems on the network, this would be a major problem. A solid management platform with an open architecture is a requirement since QoS requests are not often recognized between operators. Solutions must


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guarantee bandwidth for their signal at all times, which is key to providing the "it just works" reliability that consumers have come to expect from their television sets. So how do you send hundreds of channels out to an IPTV subscriber with a DSL line? The answer is to send only the required streams. When a user changes the �channel� on the set-top box, the STB does not "select" a channel like a typical cable system. The box switches channels by using the IP Group Membership Protocol (IGMP) v2 to join a new multicast. When the local office receives this request, it checks to ensure that the user is authorized to view the new channel. It then directs the routers in the local Central Office (CO) to add that particular user to the channel's distribution list. As a result, only signals that are currently being watched are being sent from the CO to the DSLAM, PON, etc. and to the consumer. No matter how well-designed a network may be or how rigorous its QoS controls are, there is always the possibility of errors creeping into the video stream. A robust management and operational root cause solution is key! For unicast streams this is less of an issue; the STB can simply request that the server resend lost or corrupted packets. With multicast streams, it is much more important that the network is well-engineered and fault isolated from beginning to end. As the user's set-top box only subscribes to the stream, it can make no requests for additional information. To overcome this problem, multicast streams incorporate a variety of error correction measures such as forward error correction (FEC), in which redundant packets are transmitted as part of the stream. This is an example where owning the entire network as well as proactive management and error isolation is important since it allows a company to guarantee the safe delivery of streams from one end of the network to the other without relying on third parties or the public Internet. Though multicast technology provides the answer to transmitting content out to millions of subscribers at the same time, it does not help with video on demand, which requires a unique stream to the user's home. To support VoD and other services, the local office can also generate a unicast stream that targets a particular consumer and draws from the content on the local VoD server that is typically on local storage. This stream is typically controlled by the Real Time Streaming Protocol (RTSP), which enables DVD-style control over a multimedia stream and allows users to play, pause, and stop the program that is being watched. Bandwidth capacity is not the only predictor of an operator's success in accommodating the requirements of the evolving digital home. The operator's access network platforms must enable flexibility, bandwidth management, error determination and isolation to an extent previously reserved only for equipment residing in the network core. Time-shift TV, also known as network Personal Video Recorder (nPVR), coupled with network-wide VOD, expands the concept of "watching TV" to include higher levels of interaction and control. Essentially, Time-shift TV enables subscribers to pause and rewind interactive services. The downside of the unicast model is that the network must accommodate all of this new content and performance can be impacted if it does not support multicast and unicast transition throughout (for both core and access).


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The Internet Group Management Protocol (IGMP) has a solution for carriers concerned about how to provide the greatest possible flexibility in their network. The goal is to enable a subscriber to request a program that is already being delivered to other subscriber(s). That request will result in shared distribution of the program (the subscriber joins the appropriate multicast group). IGMP will conserve bandwidth by eliminating the need for identical instances of a program to traverse the network. IGMP protocol is an Internet protocol that enables DSLAMs, PON Optical Line Terminals (OLTs), and routers to passively "snoop" subscriber traffic in order to identify and properly assign multicast group membership. An access platform with this functionality checks IGMP packets, picks out the group registration information, and configures multicasting accordingly. Without IGMP snooping, multicast traffic is treated in the same manner as broadcast traffic, that is, it is forwarded to all ports. Using IGMP snooping, multicast group traffic is only forwarded to ports servicing members who belong to that particular multicast group. IGMP snooping generates no additional network traffic, allowing carriers to significantly reduce network congestion. IGMP also needs to be managed, which is critical to a successful deployment. Bandwidth management is another critical component of successful IPTV deployment (the most bandwidth-intensive deliverable to the digital home). To facilitate consistency with their network management and load-monitoring practices for other less bandwidth-intensive applications like telephony and high-speed Internet access, carriers must select IPTV systems with management tools that enable them to carefully monitor control and error isolation and predict the results of network oversubscription rates. These tools must proactively alert them to adjust the oversubscription ratio/capacity to meet their service commitments. Average subscriber viewing behavior, relative to peak viewing behavior, along with unpredictable peaks and surges (disaster coverage), must be anticipated and bandwidth allocation made flexible. These monitoring and modeling tools must communicate with a comprehensive Unified Management System (UMS) that enables rapid alerts and response to potential network problems. See typical IP network on following page.

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New Paradigm � A Distributed IPTV Model The carrier's goal is to minimize the amount of traffic that must traverse the core network. A centralized model is the worst possible scenario from a bandwidth management/utilization perspective in a large-scale deployment. Ironically, this model is often depicted in network topology diagrams illustrating IPTV deployments. In this model, a centralized "super-headend" combines encoders, back office servers, and VOD servers. Regardless of whether the network is delivering live TV, VOD, or Time-shift TV (essentially the same as VOD the instant it switches from multicast to unicast), all content and network traffic resulting from subscriber requests must traverse the entire network from the super-headend all the way to each subscriber's Set-Top Box (STB). By changing their network topologies to encompass a flexible, distributed model, carriers will realize huge advantages, particularly for VOD and Time-shift TV. Unlike the centralized model where single-source encoding takes place at the super-headend and is then multicast throughout the network, a distributed model utilizes regional head-ends so that local content (community interest / news) is only distributed in-region. This unburdens the core and access networks. While an IPTV network does have the advantage of enabling local content to be viewable outside of region, there is substantially less demand for this programming and it would be more suitably delivered via unicast stream. Most of the actual traffic that traverses an IPTV network is going to be from live TV and subscriber requests (authentication / billing information / Electronic Programming Guide (EPG)). Authentication, EPG, and billing can be distributed as well. Content storage and distribution mechanisms are the final components of a successful IPTV delivery. Since maximum distribution is the key to creating flexibility, it stands to reason that a segmentation scheme, in which sequential content segments are distributed piecemeal, would radically reduce network congestion. Rather than sending multiple iterations of content in its entirety from one storage and streaming server to another in a segmented content solution, adjustable segments replace large files. Content segmentation at the edge, coupled with innovative protocols like Broadband Media Distribution Protocol (BMDP), which enable the IPTV system to adjust storage and distribution according to trends in subscriber behavior, provides a buffer against network jitter and a greater tolerance for peak bursts in traffic. IPTV means new revenue for carriers, and its differentiated services suggest a huge potential benefit for both carriers and their subscribers. With the arrival of virtually infinite VOD and Time-shift TV, the industry is poised to witness the first radical advances in television since digital cable. However, while subscribers are accustomed to occasional service quality variance due to traffic latency for streaming video applications on their computers, they will have limited tolerance for similar issues that affect their long-familiar TV watching experience. After all, people do not subscribe to services based on technology, they subscribe based on quality of service, value, differentiation, and convenience. IPTV requires careful selection of new technology solutions that will ensure successful initial implementation, manageability, root cause analysis, error isolation, end-to-end management and scalability, enabling carriers who plan correctly to progress to their own cycle of optimization.


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IPTV Management and Monitoring - Network Architecture Challenges Networks supporting IPTV rely on a number of technologies and protocols that provide the required levels of performance, reliability and quality of service. Many of these protocols discussed in previous sections are interrelated and are stacked one on top of the other, with many interdependencies.

Examples of the various transports, protocols and interfaces include Optical transport (SONET/SDH, DWDM), MPLS, VPLS, Ethernet and Gigabit Ethernet, IP, IP Multicast, Ethernet Multicast, GPON (Gigabit Passive Optical Network), VDSL, Residential Gateways and Set-Top Boxes (STB) among others.

The success of any service delivered over such a complex architecture is reliant on the dependencies of one layer of service on all the underlying layers. For example, a protocol that rides over another protocol (such as Ethernet over DWDM) has a dependency on it. Mis-configurations and failures in the lower level protocol will cause problems in the upper layer transport. The specific set of dependencies will vary at different points in the network, depending on the specific protocols in use there. The diagram that follows illustrates a possible set of dependencies at the edge of the core and in the access network.

To maintain video connectivity, each of the supporting protocols has to be properly operational wherever used along the video path. Since the protocols are usually layered, each layer may mask the underlying layer and thus limit visibility to any errors or performance issues that may arise.

These dependencies make the management of highly complex IP-TV Next Generation Networks very difficult. It is critical to develop and implement an approach to efficiently and quickly isolate problems that can be easily masked by the higher and lower level protocols.

See layered protocols on an IP network on the following page.

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IPTV NGN Management Challenges and Best Practices

This section describes the challenges and best practices that operators have experienced in managing IPTV Next Generation Networks. In addition, we will also discuss the associated Best Practices required to address service supply to create a highly reliable and manageable infrastructure. Table 1 - IPTV Challenges, Best Practices and Solutions are listed below. The best practices will be detailed in subsequent sections; and will be highlighted in Italics.

Table 1 - IPTV Challenges, Best Practices and Solutions

Challenges Best Practices Solution

Root Cause Analysis

- Optimize manageability, availability and performance

- Keep pace with network complexity and dynamic environments

- Reduce or minimize downstream suppression

- Optimize the diagnosis of problems

Automatic Root-Cause Analysis through Codebook

Correlation Technology

Deploy a robust information model

- Provide end-to-end management

- Correlate and integrate across various OSS�s (Operation Support Systems)

- Include relationships between business goals and IT

- Provide a single common information model

The ICIM Common Information Model

Align NGN and IPTV technology to business

level requirements

- Abstract network, application and business relationships

- Analyze problems as they relate to the business

- Automate problem resolution to achieve a higher ROI

EMC Smarts® Business Insight


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Challenges Best Practices Solution

Scalability

- Distribute components closely to the systems being managed

- Remove time-critical computational processes from the critical paths

-Utilize a process that leverages fast correlation algorithms

-Utilize Multithreading and Asynchronous processing

- Monitor selectively

- Effectively utilize memory caching technology to minimize navigation

- Smooth traffic burst through asynchronous buffering

-Distribute data and analysis through a tiered partitioned management infrastructure

EMC Smarts distributed architecture

Open Integration

- Support open API�s that allow other OSS systems to receive topology and events from any source, and supply topology and events to any destination

EMC Smarts distributed architecture

MPLS Management

- Correlate transport, MPLS and VPN/business domains for any supported topology

- Complete management tasks to implement support -driven management of all MPLS IP VPN specific requirements

EMC Smarts MPLS Manager

Optical Network Management

- Offer dynamic multi-vendor support

- Employ robust end-to-end visibility

EMC Smarts Optical Transport Manager


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Best Practices in Root Cause Analysis Next generation networks are more difficult to manage. The number and heterogeneity of hardware and software elements in networked systems are increasing exponentially thus increasing the complexity of managing these systems in a similar growth pattern. The introduction of each new technology adds to the list of potential problems that threaten the delivery of network-dependent services. As any NGN-supporting IPTV manager can attest, fixing a problem is often easy once it has been diagnosed. The difficulty lies in identifying the root cause of the myriad of events that appear on the NGN�s management console. It has been shown that 80 to 90 percent of downtime is spent analyzing data and events in an attempt to identify the problem that needs to be corrected. For NGN managers charged with optimizing the availability and performance of large multi-domain networked systems, it is not sufficient to collect, filter, and present data to operators. Unscheduled downtime directly affects the bottom line. There is a critical need for applications that apply intelligent analysis to pinpoint root-cause failures and performance problems automatically, especially in the consumer driven video and audio vertical. Only when diagnosis is automated can self-healing networks become a reality. There are many types of problems that threaten service delivery: hardware failures, software failures, congestion, loss of redundancy, and incorrect configurations. Best practice: effective root-cause analyses techniques must be capable of identifying all those problems automatically. This technique must work accurately for any environment and for any topology, including interrelated logical and physical topologies, with or without redundancy. The solution must be able to diagnose problems in any type of object - for example, a cable, a switch card, a server, or a database application - at any layer, no matter how large or complex the infrastructure. Accurate root-cause analysis is required to determine the appropriate corrective action. If management software cannot automate root-cause analysis, that task falls to operators. Because of the size, complexity, and heterogeneity of today's networks, and the volume of data and alarms, manual analysis is extremely slow and prone to error. Best Practice: intelligently analyze, adapt, and automate using a Codebook Correlation Technology described in the following sections. This Best Practice will translate into major business benefits that directly impact customers, enabling organizations to introduce new services more quickly, exceed service-level goals, and increase profitability.


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Rules-based Correlation Limitations and Challenges Typically, event managers focus on gathering and displaying ever more data to users. Because of the lack of intelligence in legacy event managers, system users often resort to developing their own custom scripts to capture their specific rules for event processing. Using customized rules is a development-intensive approach that is doomed to fail for all but the simplest scenarios in static networks. With this approach, the developer begins by identifying all of the events. Events can include alarms, alerts, SNMP traps, threshold violations, and other sources that can occur in the managed system. The Management Platform and user then attempt to write network-specific rules to process each of these events as they occur. An organization willing to invest the effort necessary to write rules faces enormous challenges. Typically, the number of network devices in a NGN IPTV network is in the hundreds or even thousands. The number of rules required for a typical network, without accounting for delay or loss of alarms or for resilience, can easily reach millions. The development effort necessary to write these rules would require many person-years, even for a small network. Changes in the network configuration can render some rules obsolete and require writing new rules. At the point in time when their proper functioning is needed most, i.e., when network problems are causing loss and delay, rules-based systems are the least reliable given their constant maintenance and update cycles. Based on the overall complexity of development, attempts to add intelligent rules to an unintelligent event manager have not been successful. In fact, rules-based systems have consistently failed to deliver a return on the investment (ROI) associated with the huge development effort.

Best Practices � Rules-based Correlation using CCT Best Practice: utilize Codebook Correlation Technology (CCT). CCT is a mathematically founded, next-generation approach to automating the correlation required for service assurance. CCT automatically analyzes any type of problem in any type of physical or logical object in any complex environment. It also builds intelligent analysis into off-the-shelf solutions and automatically adapts the intelligent analysis to the managed environment as it changes. As a result, CCT provides instant results even in the largest NGN IPTV networks. CCT solutions dynamically adapt to topology changes, since the analysis logic is automatically generated. This eliminates the high maintenance costs required by rules-based systems that demand continual reprogramming. CCT provides an automated, accurate real-time analysis of root-cause problems and their effects in networked systems. Other advantages include minimal development. CCT supports off-the-shelf solutions that embed intelligent analysis and automatically adapt to the environment.


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Any development that is required consists of developing behavior models. The amount of effort is dependant not on the size of the managed environment, but on the number of problems that need to be diagnosed. Since CCT consists of a simple distance computation between events and problem signatures, CCT solutions execute quickly. In addition, CCT utilizes minimal computing resources and network bandwidth since it monitors only the symptoms that are needed to diagnose problems. Because CCT looks for the closest match between observed events and problem signatures, it can reach the correct cause even with incomplete information. Best Practice: leverage CCT to automate service assurance provides substantial business benefits. They include the ability to implement a new service more quickly, and to achieve increased availability and performance of business critical systems. Since CCT automatically generates its correlation logic for each specific topology, new NGN IPTV services can be managed immediately and new customers can be added to new or existing services quickly. By eliminating the need for development, ongoing maintenance, and manual diagnostic techniques, CCT enables IT organizations to be proactive and to focus their attention on strategic initiatives that increase revenues and market share. CCT provides a future-proof foundation for managing any type of complex infrastructure. This gives CCT users the freedom to adopt new technology with the assurance that it can be managed effectively, intelligently, and automatically.

Best Practices - Reduction of Downstream Suppression Best Practice: reduce downstream event suppression. Some management vendors implement a form of root-cause analysis that is actually a form of downstream event suppression. Downstream suppression is a path-based technique that is used to reduce the number of alarms to process when analyzing hierarchical NGN networks. Downstream suppression works as follows. A polling device periodically polls NGN devices to verify that they are reachable. When a device fails to respond, downstream suppression:

• Ignores failures from devices downstream (farther away from the "poller�) from the first device.

• Selects the device closest to the �poller� that fails to respond as the "root cause."

Downstream suppression requires the network to have a simple hierarchical architecture, with only one possible path connecting the polling device to each managed device. This is unrealistic. Today�s mission-critical NGN IPTV networks leverage redundancy to increase resilience. Downstream suppression does not work in redundant architectures because the relationship of one downstream node to another is undefined; there are multiple paths between the manager and managed devices.


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Utilizing downstream suppression to today's NGN IPTV networks is a limited option. This technique applies only to simple hierarchical networks with no redundancy, and addresses only one problem, NGN node failure. Because of these limitations, downstream suppression offers little in the way of automating problem analysis, and certainly cannot claim to offer root-cause analysis.

Best Practices - Deploying a Robust Information Model Best Practice: employ a methodology that allows a common management platform, supporting a common information model, providing key knowledge for automating management applications. The Common Information Model (ICIM) is a potential solution. EMC�s Smarts product suite of management applications is a model for how ICIM can be used. This model is used to represent a networked infrastructure supporting complex business networks. An information model, underlying a management platform, provides knowledge about managed entities that is important to management applications such as fault, performance, configuration, security, and accounting. This information must be shared among applications for an integrated OSS solution. Best Practice: an information model must maintain detailed data about the managed system at multiple layers, spanning infrastructure, applications, and the business services typical in a NGN IPTV network. A robust information model enables solutions at every level which include element management, network management, service management, and business management. Having a common information model has many benefits. They include faster application development, stored information maintained in one place, and a single coherent view of the managed system. Applications can access the parts of the model pertinent to its operation, with consistent views to each application. In an NGN IPTV management system, agents collect operational data on managed elements (network, systems, applications, etc.) and provide this data to the management system. Best Practice: deploy an information model that represents the whole range of managed logical and physical entities, from network elements at any layer through attached servers and desktops, the applications that run on them, the middleware for application interaction, the services the applications implement, the business processes the applications support, and the end-users and customers of business processes. The classes used by the Desktop Management Task Force (DMTF) and Common Information Model (CIM) are an excellent starting point for representing the complete range of entities. An information model must also describe the behaviors of managed entities. Formalizing events and problem behaviors within the CIM is a key enabler for management automation. It plays a central role in management processing, such as real-time fault and performance management, network design and capacity planning, and other functions.


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Best Practices: data structures or repositories should play an important role in supporting the semantic model. They must be flexible enough to represent the rich set of information for each class of managed entities. They must be flexible enough to represent the often complex web of relationships between entities (logical and physical) within individual layers, across layers, and across technology domains that is so typical in a Next Generation Network (NGN). Best Practice: automate the entity discovery process and their relationships within and across technology domains. The ability to automatically populate the information repository is a definite advantage. For example, in an NGN, auto-discovery is particularly effective in environments supporting the TCP/IP protocol suite including SNMP and other standard protocols that enable automatic discovery of a large class of logical and physical entities and relationships in Network ISO Layers 1-7. Best Practice: deploy a modeling language that can describe as many entities of a managed environment as possible as well as their relationships within and across technology and business domains in a consistent manner. A high-level modeling language can simplify development of managed entity models and reduce errors. The ICIM Common Information Model� and its ICIM Repository are excellent examples of a semantics-rich common information model and an efficient information repository that meets all requirements presented in earlier sections. ICIM is based on the industry-standard DTMF CIM, a rich model for management information across networks and distributed systems. CIM reflects a hierarchical, object-oriented paradigm with relationship capabilities allowing the complex entities and relationships that exist in the real world to be depicted in the schema. ICIM enhances the rich CIM semantics by adding behavioral modeling to the description of managed entity classes to automate event correlation and health determination. This behavioral modeling includes the description of the following information items:

• Events or exceptional conditions - These can be asynchronous alarms, expressions over MIB variables, or any other measurable or observable event.

• Authentic problems - These are the service-affecting problems that must be fixed to

maximize availability and performance.

• Symptoms of authentic problems - These are events that can be used to recognize that the problem occurred.

By adding behavioral modeling, ICIM provides rich semantics that can support more powerful automation than any other management system.

Best Practices - Aligning NGN and IPTV Technology to Business Level Requirements Best Practice: build Business Services Management (BSM) solutions on a robust management platform that can automatically deliver the intelligent information needed to drive Next Generation Networks to a dashboard or management platform. Best practice solutions should be able to abstract the underlying structure, analyze and automate.


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The concept of abstraction allows a shared understanding of every piece of the environment that includes components, relationships, behaviors, and interactions across technology and business domains and across management silos.

The ICIM Common Information Model EMC Smarts Business Insight is an example of a solution that meets the challenges of modeling and abstraction with the ICIM Common Information Model�. ICIM models all physical and logical components, their relationships, behaviors, and interactions across infrastructure, applications, and business service domains. ICIM provides a unified representation of the managed environment across all EMC Smarts solutions and allows for open integration with third-party applications or external data sources.

Analysis Pinpointing root-cause problems wherever they occur and calculating their impact on business is an important aspect of the BSM process. Typical BSM tools utilize a standard event management system that collects and filters events and processes events through rules, and then displays the results. The value of the information depends on the quality of the custom-developed rules. So, without solid analysis it can deliver only raw data. Therefore, typical BSM tools are minimally useful in an organization that needs business-driven actionable information. In addition, when an alarm comes from an object in a container, the systems assume an impact on the business associated with the container. This assumption can be false, because today's systems are designed to be resilient to single points of failure. Best Practice: support built-in correlation analysis in BSM systems that can isolate service-affecting problems and their priorities. A typical solution is to utilize EMC Smarts to eliminate the need for rules by leveraging information in the ICIM Repository and patented Codebook Correlation Technology� (CCT). CCT automates the analysis of distributed systems and their business services. CCT is unique in its ability to isolate any type of problem that exhibits symptoms, in any technology. CCT can also proactively identify any exceptional condition by analyzing combinations of events and polled data.

Automation Best Practice: automate BSM processes. This reduces high-cost, labor-intensive tasks so organizations can improve service levels, increase revenue, cut operating cost, and reduce business risk.


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This is done through discovery, modeling, analysis, workflow and updating enhancements. A Best Practice for Next Generation Network BSM solutions is to quickly and accurately discover logical and physical components of the infrastructure and application layers, their relationships, and their behaviors. For example, the EMC Smarts solution for IPTV discovers thousands of different vendor products in detail.

Best Practices in Scalability Future Next Generation Network (NGN) IPTV infrastructures will be larger, more complex, and more heterogeneous. NGN�s can contain millions of network, system, application, database, storage, security, and other elements, from hundreds of vendors, configured in meshed, multi-layer network topologies with complex application and service interdependencies. In order to scale in an NGN environment, the following Best Practices apply:

• Remove computation-intensive operations from the real-time critical path • Utilize the fastest, most robust computational algorithms available

Code Book Correlation technology (CCT) is one solution. CCT pre-computes the topology-dependent correlation logic (in CCT, topology information is factored into unique problem signatures). This results in eliminating topology traversal, the most computation-intensive part of any correlation system, from the real-time critical path. CCT algorithms are orders of magnitude faster than any rules-based system. In addition to pre-computation of signatures, many other factors contribute to this speed. Correlation is a fast vector-distance operation that matches events to problem signatures. This operation is again orders of magnitude faster than searching for, retrieving, and executing all the rules that apply to each event, each time an event arrives. Correlation is key in NGN IPTV management. The complexity of Codebook is also linear in the number of managed elements it supports. The number of signatures that must be matched is proportional to the number of managed elements. In contrast, in a rules-based solution, the number of rules is exponential in the number of elements. As symptoms arrive, Codebook uses incremental processing to narrow down which authentic problems might be the root cause. Best Practice in the implementation of NGN management: use asynchronous processing and multithreading. Multithreading makes software more efficient by executing different parts of a program simultaneously. Asynchronous processing is essential for taking advantage of multiprocessor hardware architectures. As discussed, Codebook signatures are computed asynchronously with event processing. EMC Smarts solutions leverage multithreading extensively across all processing functions, including monitoring, inter-process communications, signature computation, and Codebook Correlation. For example, some asynchronous activities within a Smarts server would include


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multiple concurrent monitors, multithreaded asynchronous polling, concurrent processing of publish, subscribe actions, and query processing. Best Practice: selective monitoring. Many management tools collect all possible raw events and alarms and leave skilled operators with the task of finding the source of the problem. A tremendous amount of network and computing resources are wasted collecting these alarms, only to discard much of this data as it arrives at the management system. EMC Smarts takes the opposite approach by focusing monitoring and analysis only on those symptoms (data, events, alarms, traps) that are known to indicate service-affecting authentic problems. This substantially reduces network traffic and event processing cycles consumed by the management system. As a result, EMC Smarts' policy-based management contributes to scalability. Policy-based management allows users and subscribing client applications to further narrow monitoring by specifying object groups, the specific problems to monitor for each group, and how often to monitor them. This focus on collecting only relevant data reduces both bandwidth and CPU requirements, and allows Smarts solutions to scale to much larger environments than any other product. Best Practice: increase performance by keeping the repository in fast memory storage. As an example, EMC Smarts Common Information Model (SCIM) Repository is structured and designed to support fast navigation and access. The SCIM Repository resides in memory for fast, real-time access; and asynchronous check-pointing to stable storage ensures reliability and fault-tolerance. Best Practice: buffer events and other related data for high or burst event rates. As an example, EMC Smarts implements buffering to prevent loss of real-time data and events. In situations where thousands of events occur simultaneously, events are buffered as they arrive. Buffered events are asynchronously retrieved and processed as quickly as possible, optimally smoothing out traffic bursts. Scalability Requirements for Managing Next Generation Networks Best Practice: provide a seamless integration solution of various distributed processes into a single system image. Conversely, it is also important to integrate the distributed results, and present users and other clients with a single system image. Presenting a single system image hides the fact of distribution altogether, so that the collection of distributed processes appears as part of a single larger process. There are many advantages to this approach, including the flexibility to change partitioning within a domain as needed without affecting any process that communicates with the domain manager. Providing a single system image is not a trivial undertaking, since it requires supporting multiple levels of abstraction within a common information model. This allows the same object to be represented more or less abstractly. EMC Smarts supports a single system image of distributed cooperating managers. It leverages the Smarts Common Information Model to support seamless roll-up across any number of tiers.


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In moving to a successively higher tier, information is represented at a higher level of abstraction, and details are dropped. Best Practice: provide flexible distribution schema. When designing a distributed NGN IPTV management implementation, an architect should have the flexibility to define the boundaries of a domain managed by a management entity. One solution is to divide responsibilities by topology. For example, domain boundaries can be aligned with topology boundaries such as geographic regions, operations centers, organizational responsibilities, etc. EMC Smarts can distribute the load of a single Smarts server among two or more Smarts servers. The administrator can configure the discovery filters of the distributed servers to divide the topology among them. An EMC Smarts Service Assurance Manager configured as a client of these distributed servers can automatically synchronize both their topology and analysis results, presenting a single system image of the combined domains. NGN IPTV service providers can use Smarts to manage their ATM/Frame Relay core and IP network; and VPN services can integrate EMC Smarts MPLS Manager into their deployments. Best Practice: build operational flexibility into a Next Generation Management solution. One method is to architect a solution that is distributed as discussed above. An organization can architect the solution to fit its operational, geographic, or organizational structure, and can incrementally add new solutions to enhance management functionality without disrupting existing management solutions.

Best Practices in Open Integration In developing a Next Generation Network Management platform, one of many Best Practices is to support an open platform allowing customization, monitoring, analysis and problem management. One would also want to define automated responses and escalation policies and associate them with instances of events and service-affecting authentic problems as well as add support for new vendor products. Best Practices: leverage information maintained in a Common Information Mode (CIM) repository to develop new applications such as inventory and asset management, provisioning, and capacity planning. In terms of the common information model, it would be beneficial to refine existing library models to enrich automated analytics, or create new classes of managed entities to new technology domains. EMC Smarts� advantage is customization that is used not to develop basic functionality, but rather to enhance this functionality by leveraging the knowledge and capabilities resident in Smarts to respond to unique business needs. Best Practice: auto-discover objects in a NGN IPTV network. Defining management, as it is related to discovery, is also important. Auto-discovery should provide fine control of what is and what is not discovered. EMC Smarts provides console-based controls for setting auto-discovery


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parameters in fine detail. Auto-discovery can be manually initiated, periodically scheduled, or automatically triggered upon receipt of network change events. Best Practice in supporting Next Generation Networks Management Open Integration: add support for new vendor products. EMC Smarts has the ability to add support for various vendors. This is done through the Smarts Mediation layer. Smarts mediation technology makes it possible for the Smarts system to stay current as new products enter the market. Partners and customers can easily extend Smarts' coverage without developing any code. The EMC Smarts ICIM Common Information Model provides a common semantic framework for all Smarts solutions allowing ease of integration for existing and new vendor product solutions. Best Practice in supporting Next Generation Networks Management Open Integration: interface with other software. Information can be imported or exported to and from the repository programmatically through some form of Adapter. EMC Smarts has the ability to link to other applications through EMC supported adapters. These adapters link EMC Smarts to management tools and OSS/BSS systems that exist in a managed environment management solution. EMC Smarts Adapters deliver events, topology, inventory, and analysis results into and out of EMC Smarts Service Assurance Manager. Best Practice: extend beyond interfacing with other software products. Users can leverage the existing NGN management technology to build entirely new applications to meet their business needs. EMC Smarts has the ICIM Repository which maintains a wealth of information on the managed system that can be leveraged in a variety of applications beyond real-time operations management. These applications include inventory and asset management, provisioning and service activation, simulation, capacity planning, and many others. The ICIM Repository provides a powerful set of operations for query and update. These operations are available through a variety of Smarts interfaces including command line, ASL, Java, C, C++, XML, Perl, and others. Users can easily add or delete instances of classes or sub-classes, change the value of attributes or relationships of any instance, create new relationships between instances, and traverse existing relationships to identify related objects.

Best Practices in MPLS Management Best Practice: manage NGN IPTV network MPLS VPN implementation via a partition so that management can manage each domain both individually and in correlation with other domains. For example, similar domains include the transport domain, including Layers 1, 2, and 3, the MPLS domain, including LSPs and their related policies and the VPN and business domain, including VPN membership and topology. EMC Smarts partitions these various domains in a similar manner. It integrates and correlates information across these domains by leveraging the EMC Smarts ICIM Common Information Model�. Each domain is responsible for a portion of the model, and domains overlap at specific points. The points of overlap are entry points for passing information across domains. EMC Smarts MPLS Manager manages elements of the PE (provider edge) and CE (customer edge) routers that are related to the VPN offering. It holds a detailed view of the VPN membership and


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VPN topology, including peering relationships between PE routers, VPN membership subscription of CE routers, control protocols between PE's and their attached CE's, and complex virtual router configurations. EMC Smarts� transport domain managers (such as Availability and Performance Managers for IP, ATM/Frame Relay, SONET/SDH/DWDM, etc.) auto-discover Layer 1, Layer 2, and Layer 3 topology, both logical and physical, out-of-the-box. This includes identifying Layer 2 connections between components in the transport infrastructure, including the provider's network and the customer edge. It analyzes root causes of both connectivity and performance faults in the underlying transport domain and their impacts on other entities within the transport domain, as well as on entities in the MPLS and VPN domains.

Best Practice in Optical Network Management In order to manage Next Generation Network optical transports, a set of Best Practices is required. Best practice: offer support for a wide range of Layer 1 products with varying capabilities and attributes to provide carriers with varying approaches to sending signals up through the layers of the Open Systems Interconnection (OSI) stack. Smarts Optical Transport Manager (OTM) addresses this need with a solution for managing optical networks. Like other Smarts solutions, Optical Transport Manager leverages the EMC Smarts Common Information Model�, which places all network entities and events in the proper topological and business context. EMC Smarts Optical Transport Manager�s approach starts with authentic problems� that must be detected to protect service delivery. Not every event is a service-affecting problem. In fact, a flood of events could occur without there being a problem that needs to be fixed. Identification of authentic problems focuses on a unique set of symptoms, known as problem signatures. EMC Smarts Optical Transport Manager constantly monitors for symptoms of authentic problems. When a match between events and the signature of an authentic problem occurs, EMC Smarts Optical Transport Manager sends a notification that the problem occurred and invokes an associated action. Examples of physical objects include network elements, interfaces, and optical links. Examples of logical devices include Common Transport Protocols (CTP's) and protection groups.

Conclusion

This paper discussed the challenges and Best Practices to manage large complex network and application infrastructures for IPTV and Next Generation Network (NGN) services.

The greatest challenges IPTV operators face as they deploy IPTV and other broadband services is offering reliability and quality of service while dealing with the myriad of layered transport, protocols, physical infrastructures and applications. In addition, visibility into these layered protocols is a major challenge.


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Getting video-over-IP equipment from different manufacturers integrated into existing metro and access networks continues to be a challenge.

Video service delivery places high bandwidth demands on its network and related applications as the provider integrates storage, delivery and access to the consumer. The scalability requirements are enormous and can include thousands of servers with back-end storage in the petabyte range.

As discussed, Networks rely on multiple layered protocols such as MPLS, Ethernet, IP and Multicast. Since the layers are independent, a problem in a lower protocol can be masked as well as spread to the other protocols. This type of lower level protocol disruption can be easily hidden and difficult to diagnose. In networks of this size, it is important that a diagnosis be timely, easy to isolate and that the solution is accurate.

The EMC Smarts family of solutions, including support for IPTV, helps service providers create a high availability and high performance environment. Best practices state that Smarts� powerful modeling, cross-domain correlation, analysis plus a scaleable and distributed architecture make the EMC Smarts family of solutions capable of supporting and managing large, complex environments.


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Appendix A � Abbreviations

3G Third-Generation Mobile: general description of new mobile technologies API Application Programmers Interface ATM Asynchronous Transfer Mechanism BSS Business Support System CE Customer Edge Router in a MPLS network CIM Common Information Model CRM Customer Relationship Management DSL Digital Subscriber Line: Access Technology DSLAM Digital Subscriber Line Access Multiplexer DWDM Dense Wavelength Division Multiplexing: fiber-optic transmission technique ICIM EMC Common Information Model EMN Element Management System IETF Internet Engineering Task Force: standard organization IPTV Television over IP ISIS Intermediate System to Intermediate System Protocol: IP protocol ITIL IT Information Library: Guideline for Best Practice in IT environment ITU International Telecommunication Union: Standardization organization LSP Labeled Switch Path: End-to-End connection in a MPLS network MIB Managed Information Base MoM Manager of Manager MPLS Multi-protocol Label Switching: network technology MSAN Multi-Service Access Networks MTNM Multi-Technology Network Management: object model of the TMF MTOSI Multi-Technology Operations System Interface: standard interface the TMF works

on NGN Next-Generation Network NGOSS New Generation Operational Support Systems: Initiative of TeleManagement Forum NMS Network Management System NOC Network Operation Center NPVR Network-based Private Video Recorder: service offering OIPV Over IP Video: service offering OSPF Open Shortest Path First: IP protocol OSS Operational Support Systems P-Router Provider Router in a MPLS network PBX Private Branch Exchange PE Router Provider-Edge Router in a MPLS network QoS Quality of Service ROI Return on Investment SDH Synchronous Digital Hierarchy: transmission technology SID Shared Information Data: standard framework from TeleManagement Forum SLA Service-Level Agreements: part of Service-Level Management SLM Service-Level Management SNMP Simple Network Management Protocol: standard protocol to manage IP devices TL1 Standard Interface between network equipment and management systems TMF TeleManagement Forum; standard organization TMF814 Solution Set for the Multi-Technology Network Management Interface


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VoD Video on Demand: service offering VoIP Voice over IP: service offering VPLS Virtual Private LAN Service: VPN service on layer 2 VPN Virtual Private Network VRF Virtual Routing Forwarding WiFi Wireless Fidelity: wireless access technology WiMAX Worldwide Interoperability for Microwave Access: wireless access technology


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Appendix B � References

All listed documents are part of EMC�s Technical Library and are accessible via www.emc.com/techlib/. Look for �EMC Smarts� under the section �Software�.

[1] Scalability Requirements for Managing the World�s Most Complex IT Systems: EMC Smarts Distributed Architecture , EMC Engineering White Paper, December 2005

[2] The ICIM Common Information Model , EMC Engineering White Paper, October 2005

[3] Automating Root-Cause Analysis: Codebook Correlation Technology vs. Rules-Based Analysis, EMC Engineering White Paper, October 2005

[4] EMC Smarts Business Insight , EMC Engineering White Paper, October 2005

[5] EMC Smarts IP Availability Manager , EMC White Paper, December 2005

[6] EMC Smarts MPLS Manager: Innovative Technology for MPLS/VPN Management , EMC Engineering White Paper, December 2005

[7] Managing Next-Generation Networks: EMC Service Assurance for new IP Services, EMC Engineering White Paper, September 2006

[8] EMC Smarts Optical Transport: A Manager of Managers for Ensuring Service Delivery over Optical Networks, EMC Engineering White Paper, January 2006

[9] EMC Smarts Openness: Options for Customization, EMC Engineering White Paper, November 2005

[10] Next Generation Network Development in OECD Countries, January 2005

[11] Making IPTV A Reality: Optimizing the Network for Digital Media Services, Digital Design Line, December, 2006, By Kay Benaroch

[12] An introduction to IPTV, By Nate Anderson, March 12, 2006

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