turning ip video distribution into reality - fujitsu · delivery models—while eliminating risk...

Turning IP Video Distribution into RealityAn Architectural and Economic Overview

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FUJITSU NETWORK COMMUNICATIONS INC.2801 Telecom Parkway, Richardson, Texas 75082-3515Telephone: (972) 690-6000(800) 777-FAST (U.S.)us.fujitsu.com/telecom

OverviewAs a service provider, you know your world is changing. Wireline voice revenue is declining, and traditionaldata services such as frame relay and ATM no longer meet the demanding requirements of enterprisecustomers seeking network-based managed services supporting any-to-any connectivity. Your residentialcustomers are threatened by MSOs offering triple play services, including but not limited to video ondemand. And emerging enterprise-computing paradigms, such as strategic outsourcing and Gridcomputing, are changing the way your customers think about network services.

As your customers and their mission-critical applications change, so do network technologies. A number ofemerging technologies have matured and are ready for network deployment. These technologies, such asMPLS–based Optical Ethernet transport and QoS capabilities, promise to help you deploy a number of newservices, including IPTV, VoIP and packet voice, Ethernet E-Line (point-to-point) and E-LAN (multipoint)services and network-based managed IP services.

How do you respond to these changes? Clearly, the deployment of overlay networks in support of newservices will no longer suffice. Instead, you must focus on transition or profitably migrating your existingnetworks to respond to these changing customers, changing applications and changing technologies in anincreasingly competitive environment. You need a transition strategy that successfully supports thefollowing objectives:

• The deployment of new, profitable network-based managed IP and Ethernet services• The ability to seamlessly migrate traditional data services to a converged packet infrastructure• Service differentiation and competitive advantage• Achievement of operational efficiencies through the deployment of a service-oriented OSS architecture

The concept of transition raises an important question: how will you maintain critical legacy revenuestreams, meet your growth objectives and increase profitability? The answer is not as simple as a networkupgrade. Any strategy to achieve these goals must begin with the effective transition and integration ofthese emerging technologies into the existing network architecture.

Fujitsu offers long-term experience in guiding network transitions, which enables our customers toleverage this expertise to their benefit. Our previous experience with transition suggests the appropriateapproach is a holistic evolution—an evolution that extends and leverages your existing infrastructure andprovides for a seamless integration of new services activation within the confines of the existing OSS/BSSback office systems, avoiding forklift deployment.

To help solve these challenges, Fujitsu has developed FASST™ with you, the service provider, in mind. FASST,executed as a strategic partnership of companies led by Fujitsu, is an architecture and solution setoptimized for transition management. FASST enables you to manage the multitude of transitions you needto execute in order to differentiate yourself from your competitors through new services and servicedelivery models—while eliminating risk and leveraging your multi-billion dollar investments in SONET,IP/MPLS and OSS. A key element of this transition is the migration of existing corporate data services andthe introduction of profitable new managed services. In short, FASST enables Transition withoutCompromise.

For your convenience, a list of acronyms can be found at the end of this document.

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Turning the Vision of IP Video Distribution into RealityFASST is, in essence, our vision for how to transition your network to a service-oriented architecturesmoothly and without compromise. This White Paper specifically outlines the key aspects of the Fujitsu IP Video Distribution Architecture and demonstrates how your network infrastructure can beevolved and continuously streamlined.

Facing pricing pressures on traditional telephony services, many telecom carriers are being advised topursue a voice, video and data combination to acquire new residential customers, as well as to avoid theloss of current customers. MSOs are aggressively discounting additional services beyond basic cable andbroadband Internet, such as VOD and IP telephony. The mainstream satellite providers are attempting tobranch out into data. Meanwhile, the network vendor community and trade press are buzzing over theprospects of cable and telephone companies offering triple play services, regardless of the unfulfilledrevenue promises from years past.

Fujitsu believes an MPLS-enabled Layer 2 multicast approach addresses the technical requirements, as wellas all of the critical business issues impacting the ability of service providers to offer residential broadcastvideo. In addition, we believe the Fujitsu Reference Architecture, as shown in Figure 1, provides aninnovative, differentiable and cost competitive video offering to its subscribers. The following sections setforth the Fujitsu Reference Architecture in comparison to various reference architectures by the DSL Forumand ITU-T. The sections also provide several case studies to support the viability of the Fujitsu approach.

Figure 1: The Fujitsu Reference Architecture for Video Distribution

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The Fujitsu Reference Architecture for Video DistributionThe Fujitsu Reference Architecture uses an MPLS-enabled Layer 2 multicast approach (P2MP LSP), deployedover a carrier-grade Optical EAN. Multicast services are supported over P2MP connections, allowing aconnection-oriented approach for the multicast services, in contrast to connectionless forwardingemployed in general IP multicast networks deploying PIM, either in PIM-DM or PIM-SM.

The P2MP connection is MPLS-based in the core of the EAN (i.e., P2MP LSP) and is implemented by aconnection-oriented VLAN stacking solution in the access rings, where MPLS is not used. The P2MP LSP canalso be established by signaling protocols such as RSVP-TE but is currently established by ASPEN®, theelement and service provisioning manager of the Reference Architecture.

The advantages of using connection-oriented MPLS P2MP connections for video distribution servicesinclude:

• Hard QoS and bandwidth guarantees – Since the circuit path is pre-provisioned, CAC mechanisms canbe used to reserve bandwidth for multicast circuits along the path in the correct class of service. Thisprocess guarantees the bandwidth of the multicast traffic, as well as the bandwidth for other lowerpriority traffic that may still need hard QoS and bandwidth guarantees. This approach is far superior tothe DiffServ approach of relative QoS where multicast traffic may be assigned with EF code-point butwould have impact on the traffic not marked with EF.

• Co-existence with other residential and business services –Service co-existence is made possibledue to the strict QoS approach taken throughout the network for all services, including video multicast.

• Support for 1+1 video source protection – This feature allows redundancy of the video sourceswithout any interaction between them. The network automatically switches from one video source tothe other upon any unforeseen video source failure so that TV multicast traffic is continuously beingtransmitted to subscribers. The switchover time is approximately 50 ms.

• Fast (50 ms) protection for any failure – 50 ms protection for any network link or video source failureis offered since protection is based on pre-provisioned paths and MPLS fast-reroute protection tunnels.

• Aggregation of multiple multicast groups into a single P2MP connection – This approach allows theaggregation of multiple multicast groups onto one connection and forwards all of them according to asingle MPLS label rather than separate IP multicast addresses. With this approach you do not have tomaintain a state per multicast group in each device on the network, reducing the resources needed formulticast support. In addition, when a failure occurs in the network, you do not need to wait for theconvergence of all the different multicast groups to work around the failure. Only the affected multicastgroups are switched over to the protection tunnel, along with the P2MP connections that carry thesemulticast groups.

• Layer 2 Transparency – The P2MP connections allow control protocols for the multicast traffic to becarried transparently inside the connections, without requiring the intermediate nodes to terminate orprocess them in any way.

• High security – The service provider provisions the P2MP connections and assigns the video sourceinterfaces (i.e., only these interfaces are allowed to connect video sources). This process is very differentfrom IP multicast routing protocols such as PIM in which anyone on the network has the capability tobroadcast from a video source.

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The major technical and economic benefits provided by the Fujitsu Reference Architecture include:• All the technical requirements for delivering a compelling and competitive IPTV service offering

are met.• Not all of the applications have to be forwarded to the BRAS, which reduces cost and increases network

performance.• The service control block (and optionally, the applications block) are connected to the IAN or their

corresponding provider’s network, which is consistent with the logical service architecture defined bythe TR-058 specification from the DSL Forum.

• A key difference between the Fujitsu Reference Architecture and that of the DSL Forum is that someapplications can connect directly to the EAN. Examples of such applications are video headends andVOD servers, or video streamers that are located in a local region and insert or piggyback their contentwith the national content (i.e., local TV programming).

• The deployment of additional Layer 3 Ethernet aggregation routers is not required in the distribution architecture.

• The deployment of an IOF drop-and-continue network is not required when connecting the VHO andVSO locations.

• Dual latency paths and dynamic rate re-partitioning are supported, which is required to support lowlatency data applications and very low bit error rates for video content.

• 50 ms protection is supported for Gigabit Ethernet connections from the DSLAMs. As such, you do nothave to dual home these connections.

• The number of required Gigabit Ethernet ports is reduced by more than 50%.• The number of fiber pairs for the local loop is reduced.• The Fujitsu Reference Architecture depicts a network that is easily deployed and managed, utilizing a

single element management and provisioning system.• The Fujitsu Reference Architecture anticipates the use of SIP, both to authenticate the set-top box when

it connects to the network and the channel change process itself. For example, to change channels, a SIPmessage will be relayed to the VSO Ethernet aggregation switch that will cause the channel change.

The services supported within the Fujitsu Reference Architecture support all forms of traditional triple-playservices, including but not limited to Internet access, TV channel distribution, VOD and VoIP. These serviceshave very different attributes and require different levels of QoS, which translates to provisioningrequirements around guaranteed bandwidth, bounded delay and jitter and packet loss rate. These servicesalso have different requirements for failure recovery times.

The following sections compare the Fujitsu Reference Architecture with the DSL Forum and ITU-TReference Architectures for Video Distribution.

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Video Delivery Reference Architectures DSL Forum Reference ArchitectureThe widely used reference architecture from the DSL Forum was introduced in the forum’s TR-058specification document and was adopted by the TR-059 specification document, which added furtherdetails on QoS support. The architecture is depicted below in Figure 2. Since the aggregation networkbetween the DSLAM and BRAS (i.e., the so-called Backhaul Network) in the Fujitsu Reference Architecture isEthernet-based, the ATM-based functionalities defined in TR-058 and TR-059 do not fully translate to anOptical Ethernet deployment. However, by adopting the terms defined in TR-058 and TR-059, such as Vinterface and BRAS, the Fujitsu Reference Architecture will provide a common framework for theevaluation.

Figure 2: DSL Forum TR-059 Reference Architecture

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Referring to the logical service architecture that is defined within TR-058, which is depicted in Figure 3, isalso important. We will use the term service control to indicate all the necessary components that controlthe services, which include service provisioning and network management stations, AAA servers, securitypolicy servers, resource control servers and the SIP servers, and the term applications to indicate all thenecessary components that actually provide the content or services, which include VOD content servers,DNS servers, proxy servers and game servers.

A draft document (WT-101 R2) has recently been proposed to the DSL Forum titled Migration to EthernetBased DSL Aggregation. The architecture suggested in WT-101 R2 is depicted in Figure 4.

Figure 3: The Logical Service Architecture of TR-058

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While most of the content of WT-101 R2 focuses on the required changes or enhancements to DSLAM andBRAS platforms, the draft reference architecture also describes the V interface and the requirement for theC_VLAN to distinguish customers and the S_VLAN to distinguish service types. The VLAN tag associatedwith each VLAN is called C_TAG and S_TAG, respectively. The WT-101 R2 document mandates that if bothVLAN tags are supported, C_TAG is the inner tag and S_TAG is the outer tag in the frames, as shown inFigure 5.

Figure 4: The WT-101 R2 Draft Reference Architecture

Figure 5: The VLAN Stacking Requirement of WT-101 R2

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The specifications and functionality proposed by Fujitsu constitute a superset of the previously mentionedframeworks in the context of the QoS objectives that a state-of-the-art video distribution network shouldachieve. In other words, the Fujitsu Reference Architecture can meet a key superset of requirements asdefined within TR-058, TR-059 and WT-101 R2.

ITU-T Reference ArchitectureThe ITU-T working group WG3 has proposed an architecture in its draft recommendation TR.123.qos.Notably, the recommendation defines two levels of traffic aggregation. The first level is Ethernetaggregation, which is provided at Layer 2 and corresponds to the EAN set forth within the DSL Forumreference architecture. The second level of aggregation is IP aggregation, which is provided at Layer 3 andcorresponds to a regional or national IP network.

Figure 6: ITU-T TR.123qos Draft Reference Architecture

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The major objective of this draft architecture is to investigate and define the QoS control mechanisms foran IP access network, focusing on network topology, status information collection and resource allocation.The draft architecture does not particularly define the functionality of the EAN but does derive themechanisms for its Ethernet aggregation from MEF specifications. TR.123.qos also requires two VLAN tagsin order to distinguish customers and aggregate traffic of the same attribute (e.g., the type of traffic). Thisprocess is similar to the specifications of the V interface described in the WT-101 R2 draft.

The arrangement of the two VLAN tags (as depicted in Figure 7) provides for an A_TAG and C_TAG. Whilethis approach looks at first glance to be similar to the WT-101 R2, the meaning of the A_TAG is muchbroader than that of S_TAG because traffic can be aggregated not only by the type of service but also byother criteria such as the type of subscriber). Figure 7 illustrates the proposed VLAN arrangement.

Figure 7: The VLAN Stacking Arrangement of TR123qos Draft

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InterfacesTogether with the proposed network architecture, three new interfaces are introduced. They are the V+interface between the DSLAM and the EAN, the E-I interface between the EAN and the IAN, and the E-Binterface between the EAN and the BRAS. By this definition, the EAN is able to work with all DSLAMs androuters/BRAS that comply with the specifications of these interfaces.

The V+ Interface specifications include the following requirements:• The interface must be a Fast Ethernet or Gigabit Ethernet interface• The interface should support frames with a single 802.1Q VLAN tag• The interface may support frames with dual 802.1Q VLAN tags, in which case the outer VLAN tag should

be S_TAG, and the inner VLAN Tag should be C_TAG• The interface may support untagged frames• The interface must differentiate the types of traffic and mark the frames of each type of traffic in the

following ways:• By DSCP bits when the frames through the V+ interface contain no VLAN tag(s) • When the frames contain VLAN tag(s)

• By the outer VLAN tag• By 802.1p bits within the outer VLAN tag • By DSCP bits • By any combinations of the above three frame marking methods

• SIP or IGMP messages must be used over the V+ interface for multicasting control• If SIP or IGMP is used not only for TV broadcast service but also for other multicast services that may be

run by PCs, the SIP or IGMP messages over the V+ interface must be able to differentiate themselves bythe services they are used for and the differentiation must be in one of the following ways:

• By the VLAN tag that is assigned to each specific multicast service• By a unique VLAN tag that is assigned to the IGMP messages used by each specific multicast service• By the same DSCP bits in the IGMP messages as in the data packets sent by each specific multicast

service• By the unique DSCP bits in the IGMP messages• PIM-SM may be used for multicasting control; if PIM-SM is used over V+ interface, IGMP should not be

used• If two links exist over the V+ interface, they must run LAG or 1+1 redundancy• Jumbo frames (frames longer than 2000 bytes) may be supported

E-I Interface specifications include the following requirements:• The interface must be a Fast Ethernet or Gigabit Ethernet interface• The interface should be able to send all the required multicast groups from the IP aggregation network

to the EAN without receiving requests (via SIP or IGMP for example) from the EAN• The interface should support frames with a single VLAN tag• The interface may support frames with dual VLAN tags, in which case the outer VLAN tag should be

S_TAG, and the inner VLAN Tag should be C_TAG• The interface may support untagged frames

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• The interface must differentiate the types of traffic and mark the frames of each type of traffic in thefollowing ways:

• By DSCP bits when the frames through the V+ interface contain no VLAN tag(s) • When the frames contain VLAN tag(s)

• By the outer VLAN tag• By 802.1p bits within the outer VLAN tag • By DSCP bits • By any combinations of the above three frame marking methods

• Link Aggregation Group may be supported• Jumbo frames are supported

E-B Interface specifications include the same requirements as the E-I Interface.

SIP to IGMP Translation FunctionalityThe Fujitsu Reference Architecture implements a SIP-proxy behavior because it provides more functionalitythan a straightforward SIP-proxy gateway. A user-configurable option can send all SIP messages to the CPUfor forwarding and processing or identify the session control messages (e.g., INVITE, OK, BYE) and forwardthose only, while normally forwarding all other SIP messages.

In those areas of the network where SIP will only be used to control sessions, the configuration effort toidentify specific SIP messages to be sent to the CPU can be avoided, as all SIP messages will be sent to theCPU for proxy processing. In those areas of the network where SIP will be used to both control sessions andalso signal in-session activity, (e.g., flipping TV channels), identifying the session control SIP messages mayprovide better performance. SIP is a very flexible protocol with numerous options. We assume the serviceprovider will decide on a certain policy pertaining to SIP in the network, including which qualifiers must bein which packets and in what order. Such a policy will make identification feasible for implementationinside a high capacity data path such as those at 10 Gbps.

The main purpose of sending the SIP messages to the CPU is to apply admission control on the session.Both voice and video do not behave gracefully with lost packets, so the goal is to avoid congestion ratherthan to drop sessions intelligently when congestion occurs. All sessions, whether voice or video, possessQoS attributes, such as bandwidth requirements and type of session, which can be compared against theavailable bandwidth on both the ingress and egress links. This process is very similar to the way that anysignaling protocol for bandwidth reservation, (e.g., RSVP-TE) is treated. If the available resources aresufficient to accommodate the newly requested session, the CAC database is updated, and the session isallowed. The actual resource reservation is done upon receipt of the OK message from the server, althoughthe CAC operation is performed in both directions.

This process supports control messaging in both directions. For instance, if on the way from client to server,enough resources are not available for the session, the request is not forwarded to the SIP server. Instead, anegative response is composed and sent back to the client.

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Other situations occur when SIP packets are sent by one end but do not arrive at the other end. To copewith such situations, the Fujitsu Reference Architecture maintains the status of active sessions and sendsmessages on behalf of the server or client to reflect the true state of the session to the receiver. This featureis very important, as it helps facilitate the appropriate utilization of resources, as resources are notmaintained for inactive state sessions. State awareness is also vital for the proxy implementation toproperly use internal resources. For example, the proxy implementation must be able to tell a new messagefrom a re-transmission of an old message.

Contrary to legacy SIP proxy implementations, whose main purpose is to enable connectivity, the FujitsuReference Architecture proxy has another vital task – admission control. Therefore, while other proxies maynot be interested in any more messages after the call has been established, the Fujitsu ReferenceArchitecture proxy continues to accept and process all messages for the duration of the session. As such,the proxy will not miss events such as bandwidth modifications or call terminations, which is mandatory inorder to provide accurate admission control and dynamic rate re-partitioning.

Figure 8: SIP to IGMP Translation Points – Fujitsu Reference Architecture

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The Economics of Video DistributionThe concept of Internet bypass is quickly becoming the future of video distribution. Tom Wolzien ofBernstein Research coined this term in a research report titled Pipe Dreams: Media's Exploding Capacity,which was released in May 2004. Wolzien suggests in Pipe Dreams that in a world of TiVos and Internet-connected TVs, bypassing the traditional MSOs and connecting directly to consumers via the videodistribution architectures that are being built by the ILECs, will be economically and technologicallyfeasible for content providers.

This point suggests that the content providers will choose ILEC partners who can provide cost-effectivevideo distribution. As such, a video distribution architecture not only must provide video-quality QoS butalso offer a highly competitive price point on a per-subscriber basis.

The functional capabilities of the FASST Video Distribution Architecture provides the opportunity to offer adiverse range of content and data services addressing the requirements of multiple markets, including theEnterprise and residential marketplace, from a single footprint—allowing a service provider to lower theCAPEX and OPEX cost on a per-subscriber basis and to increase the addressable revenue per dollar ofCAPEX and OPEX.

This FASST Video Distribution Architecture approach offers a comprehensive suite of solutions that enablea breadth of data services to all of your customers, extending from broadband subscribers in the suburbs toEnterprise customers in Class A office buildings. The architecture must also support a wide range of accessinterfaces so that customers can connect regardless of fiber availability or geographic location.

Each customer interface has to support common Advanced Subscriber Management functions, QoSfeatures, and per-flow accounting, further ensuring the consistency of the user experience and theenforcement of service level agreements.

The following sections compare the economics of the Fujitsu Reference Architecture with competingarchitectures and set forth the appropriate business metrics which service providers should consider in thecontext of a selection process.

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The FASST Economic Advantage

Architectures for Narrowband or Broadcast Services This section focuses on certain baseline architectures designed for telephony or broadcast video serviceprovisioning: HFC, DLC and FTTP.

HFC ArchitectureThe HFC architecture employs a combination of both fiber and coaxial cable. HFC employs a fiber backbonethat corresponds to the fiber feeder in the DLC and the FTTP networks. HFC can be used to deliver bothdistributed video and telephone services and can carry up to 500 channels (for a 500 home node, implyingone channel per home). In addition, HFC systems can simultaneously support VOD and telephony. Forbroadcast transmission, HFC provides each subscriber with the same group of video channels, therefore, ahigh sharing of resources exists. The HFC headend receives signals from local studios, over-the-airbroadcasts, or microwave and satellite sources and combines and re-transmits these signals over the trunk(or feeder) cable of the network. Portions of the signal are split to feeder cables and then to drop cables toserve the household.

The HFC distribution plant consists mainly of coaxial cable. Because of the large attenuation of signals overcoaxial cable, feeder amplifiers (mini-bridgers and line extenders) are necessary to amplify the signal forboth forward and return paths. Passive equipment includes taps, connectors, 3-way splitters, powerinserters and directional couplers. Sixty-volt power supplies drive the active equipment in the distributionnetwork. The drop loop consists of coaxial drop cable. Lastly, an addressable converter is needed on thesubscriber premises to deliver distributed and switched video services.

From a video distribution perspective, a Layer 3 Ethernet–optimized router is normally used to provide PIM-SM multicast support.

DLC ArchitectureDLC is a fiber-based architecture that is typically used by telephone companies to provide narrowbandtelephony, like POTS and data services. The DLC system analyzed for this paper utilizes a DSLAMterminating DSL modems over copper at the customer premises, which is then backhauled to the IOFnetwork utilizing ATM trunks. From a video distribution perspective, a multiservice Layer 3 BRAS router isnormally used to provide PIM-SM multicast support and subscriber management.

FTTP ArchitectureAn FTTP archtecture is very similar to a DLC system. In an FTTP system, fiber is extended past the node andto the home. This process offers several advantages: first, FTTP exploits the high capacity of fiber by sharingthe transmission facilities over more subscribers in the distribution network and second, by deploying morefiber, FTTP lowers the incremental investment needed for broadband services. In an FTTP system, remoteelectronics, referred to as a host digital terminal, take a high bit rate signal from the CO terminal anddemultiplex the signal via a fiber bank assembly onto lower bit rate distribution fibers.

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This architecture is well suited for reliable delivery of video, telephony and data services. A key differencebetween the HFC and the FTTP architectures is the means used to transport digital signals from the remoteterminal to the curb. FTTP uses baseband transport of digital signals over low noise fiber. HFC requires themodulation of an RF carrier with the digital signal for transmission over coax from the remote node.

From a video distribution perspective, a Layer 3 Ethernet–optimized router is normally used to provide PIM-SM multicast support.

Economic ModelsIn this section we present an economic comparison of the Fujitsu Reference Architecture with HFC- andFTTP-based architectures when they are deployed to carry a full range of services.

A cost comparison of these architectures is based on developing accurate cost models for laying out theinfrastructures to enable them in their traditional roles of supporting interactive video services. Thearchitectures are evaluated separately, along with the incremental cost of deploying these architectures.

The incremental costs are then combined with the infrastructure costs to obtain the overall results.

AssumptionsThe set of assumptions governing the costs models are outlined below. These assumptions arerepresentative of current visions of network deployment.

• The node size is assumed to be 480 homes, along with a CO size of 30,000 homes and a networkheadend size of 180,000 homes.

• The plant is assumed to be 70% aerial and 30% underground with a 60% take rate for analog services.For modeling, the cost of the penetration rate for interactive services is set to be a variable assumed tobe less than the take rate for analog services.

• A set-top box estimated to cost $125 is needed in conjunction with an HFC network carrying broadcastanalog services. A digital set-top box, which is needed for all IVS and for enabling the all-FTTP networkto carry broadcast services, is estimated to cost $350.

• The peak coincident busy hour usage of these services is considered to be fixed at 25% of the interactiveservice penetration rate.

• IVS offerings are considered to be 70% requiring 1.5 Mbps and 30% requiring 6 Mbps, with a set-top touser ratio of 1.6. This ratio corresponds to an average bandwidth of 2.85 Mbps per IVS channel. Note thatthis ratio imposes a relatively low demand on bandwidth per channel. Demands on system bandwidthmay be higher in general and would certainly be higher if HDTV services are to be introduced.

• Routed Ethernet is considered to be the primary transport and multicast support of the HFC offering.

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The FTTP architecture used in this analysis represents a custom development carried out by broadbandtechnologies that attempts to optimize either ATM switching technology, routed Ethernet technology orDWDM technology to account for asymmetric bandwidth requirements of IVS in the forward and returndirections. Combining video with telecommunications data streams already present on the FTTP networksoffers additional optimization. From the viewpoint of cost modeling, assigning costs for a customdeveloped architecture is difficult unless detailed system designs are available. Hence, our approach hasbeen to estimate the cost of a system providing SDV functionality equivalent to that of thetelecommunications services. We treat telecommunications and video services independently, but thisassumption is not allowed to affect the cost estimate significantly. This approach is useful in providing arough estimate of the incremental cost of SDV services over FTTP and, as is shown later, is extremely usefulin comparing the general trends in cost with respect to both architectures.

The following assumptions are used in the incremental cost analysis of FTTP:• A node size of 1000 is chosen; the CO and headend size are assumed the same as for HFC.• A 100% penetration rate is assumed for telecommunications services, therefore, additional infrastructure

equipment is not required for deploying video services.

In both the HFC and FTTP instances, a cost comparison is carried out on a cost-per-home-passed basis. A40% markup is also applied to the incremental costs for interactive video services to account for installationcosts. Additionally, for comparing the cost of IVS services over the HFC or FTTC network, a suburban plant(comprising 100 homes per mile passed) is assumed, with node sizes being equivalent to those consideredfor the IVS cost modeling.

The Fujitsu Reference Architecture is analyzed using the same assumptions that were previously set forth,with the exception that Layer 2 multicast is deployed.

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Results and Economic ComparisonsFigure 9 illustrates the combined results for the scenarios outlined in the previous section. Based on theseresults, the most cost-effective solution is to use the Fujitsu Reference Architecture to carry all services.These findings primarily result from the significantly lower initial infrastructure costs for the FujitsuReference Architecture when compared with the HFC/FTTP/DLC infrastructure costs.

Figure 9: Cost Comparison of All Services over Comparison Architectures

An analysis of Figure 9 indicates that the Fujitsu Reference Architecture is the least costly at all penetrationrates between five and fifty percent, followed by the FTTP-ATM hybrid architecture. Within this same rangeof penetration rates, the remaining three scenarios have comparable costs. However, we notice that as thetake-rate increases, the cost for the remaining scenarios seem to increase at a greater rate than the FujitsuReference Architecture (beginning at the 25% penetration rate). We believe this cost differential is based onthe operational and provisioning costs incurred as a result of maintaining multiple element managementand provisioning systems for optical, routed Ethernet and ATM systems as compared to a single elementmanagement and provisioning system for the Fujitsu Reference Architecture. In addition, the utilization ofLayer 2 multicast significantly reduces (by as much as 50%) the Gigabit Ethernet ports required to supportLayer 3 PIM-SM multicast in the routed Ethernet architectures.

We also note that FTTP-DWDM costs are essentially flat with the penetration of IVS, but the start-up costsare substantially higher.

5% 10% 15% 20% 25% 30% 35% 40% 45% 50%

Penetration Rate

FTTP Routed Ethernet

DLC-ATM

HFC-Routed Ethernet

Fujitsu Reference Architecture

FTTP-DWDM3000

2500

2000

1500

1000

500

0

Co

st P

er H

om

e in

Do

llars

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ConclusionThe results of this analysis clearly indicate that the Fujitsu Reference Architecture is the most economicalapproach for provisioning video distribution, particularly at initial penetration rates. We also believe thatthe Fujitsu Reference Architecture is the best-in-class technical solution, based on the technical advantageswhich were described earlier in this paper.

FASST provides a tremendous amount of solution-level value to you as you face the challenges of how toremain viable and achieve differentiation in this competitive environment.

First, Fujitsu is applying its well-respected interoperability and certification processes to its internallydeveloped products, as well as to the alliance partner products, providing you with an extra level of qualityand interoperability for the FASST products—speeding your adoption of innovative technology.

Second, the FASST alliance opens up best-in-class technology sharing. For example, the ability to share theFujitsu expertise in stringent carrier-class infrastructure and OSS implementation with our Alliance Partners’innovations in delivering new services and delivery models. This alliance means that FASST continues toraise the bar with best-of-both-worlds solutions that fill gaps as your requirements evolve in step with yourend customer demands.

Third, while Fujitsu offers competitive and, more often, superior products, our primary advantage is that weunderstand how to build, manage and operate networks better than any other supplier. We continue tomaintain our share in our area of expertise—the optical transport industry—and our products aredeployed in every major carrier in North America. Given this competitive environment, carriers prefer to dobusiness with companies they have had a positive experience with and who they trust—companies such asFujitsu. The benefits of working with Fujitsu include:

• Mature, stable, financially-viable carrier business partner• Best-in-class optical networking platforms• Reputation for high quality and telecom network expertise• Carrier-class supply chain and delivery assurance• Unique knowledge of telecom network transitions and intimately involved in the design of our

customers’ networks• Huge installed base of mission-critical networks (300,000+ major network elements)• Nationwide 24x7x365 service and Tier 1 support• Nationwide planning, design, implementation and operations support• Interoperability and specification assurance—we test and ensure all the components of FASST are

Fujitsu certified• Business continuity in the face of disaster

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Changing customer and application requirements, emerging technologies and the need for new businessmodels are driving service providers’ requirements to transition their networks to networks that enable:

• The deployment of new, profitable network-based managed IP and Ethernet services• The ability to seamlessly migrate traditional data services to a converged packet infrastructure• Service differentiation and competitive advantage• Achievement of operational efficiencies through the deployment of a service-oriented OSS architecture

Why all this focus on transition? Transition is inevitable; how and when you transition ultimately will definethe managed services you can support, as well as your ability to profitably and competitively deploy next-generation services. To assist with this transition, Fujitsu has developed FASST, an architecture and solutionset optimized for transition management.

FASST is relevant to you because it reflects your business objectives. Fujitsu recognizes the drivers that areaccelerating the pace of transition. We have responded with a solution that allows you to provide serviceswithout boundaries; to provide value-added, network-based managed services; to manage your transitionin orderly stages; to streamline your operations; and to decrease your risk. FASST also includes the fullexperience of Fujitsu, a trusted advisor in telecommunications for more than 20 years. In short, FASSTenables Transition without Compromise.

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Acronyms

Acronym Descriptor

A_TAG Aggregation Tag

ASPEN Atrica Service Platform for Ethernet Networks

ATM Asynchronous Transfer Mode

BRAS Broadband Remote Access Server

BSS Broadband Switching System

C_TAG Customer Tag

CAC Connection Admission Control

CAPEX Capital Expenditures

CO Central Office

C-VLAN Customer Virtual Local Area Network

DLC Digital Loop Carrier

DSCP Diffserv Code Point

DSL Digital Subscriber Line

DSLAM Digital Subscriber Line Access Multiplexer

DNS Domain Naming System

DWDM Dense Wavelength Division Multiplexing

EAN Ethernet Aggregation network

EF Expedited Forwarding

E-LAN Ethernet Local Area Network

FASST Flexible Architectur for Subscriber Service Termination

FTTP Fiber To The Premise

HDTV High Definition Television

HFC Hybrid Fiber Coax

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© Copyright 2004 Fujitsu Network Communications Inc. All rights reserved.FLASHWAVE® and FLASHWAVE (and design)™ are trademarks of Fujitsu NetworkCommunications Inc. (USA). FUJITSU (and design)® and THE POSSIBILITIES ARE INFINITE™ aretrademarks of Fujitsu Limited. All other trademarks are the property of their respective owners.

Acronym Descriptor

IAN Internet Access Network

IGMP Internet Group Multicast Protocol

ILEC Incumbent Local Exchange Carrier

IOF InterOffice Facilities

IP Internet Protocol

ITU-T International Telecommunication Union-Telecommunication

IVS Integrated Video Services

MEF Metro Ethernet Forum

MPLS Multi Protocol Label Switching

MSO Multiple System Operator

OPEX Operational Expenditures

OSS Operational Support System

P2MP LSP Point-to-Multipoint Label Switch Paths

PIM-DM Protocol Independent Multicast-Dense Mode

PIM-SM Protocol Independent Multicast-Sparse Mode

POTS Plain Old Telephone Service

QoS Quality of Service

RSVP-TE Resource Reservation Protocol-Traffic Engineering (MPLS)

SDV Switched Digital Video

S_LAN Service Virtual Local Area Network

SIP Session Initiation Protocol

VHO Video Headend Office

VLAN Virtual Local Area Network

VOD Video On Demand

VoIP Voice over IP

VSO Video Serving Office

WDM Wavelength Division Multiplexer

turning ip video distribution into reality - fujitsu · delivery models—while eliminating risk...

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