Turning IP Video Distribution into Reality An Architectural and Economic Overview

Transcription

1 Turning IP Video Distribution into Reality An Architectural and Economic Overview

2 Overview As a service provider, you know your world is changing. Wireline voice revenue is declining, and traditional data services such as frame relay and ATM no longer meet the demanding requirements of enterprise customers seeking network-based managed services supporting any-to-any connectivity. Your residential customers are threatened by MSOs offering triple play services, including but not limited to video on demand. And emerging enterprise-computing paradigms, such as strategic outsourcing and Grid computing, 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 of emerging technologies have matured and are ready for network deployment. These technologies, such as MPLS based Optical Ethernet transport and QoS capabilities, promise to help you deploy a number of new services, 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 new services will no longer suffice. Instead, you must focus on transition or profitably migrating your existing networks to respond to these changing customers, changing applications and changing technologies in an increasingly competitive environment. You need a transition strategy that successfully supports the following 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 revenue streams, meet your growth objectives and increase profitability? The answer is not as simple as a network upgrade. Any strategy to achieve these goals must begin with the effective transition and integration of these emerging technologies into the existing network architecture. Fujitsu offers long-term experience in guiding network transitions, which enables our customers to leverage this expertise to their benefit. Our previous experience with transition suggests the appropriate approach is a holistic evolution an evolution that extends and leverages your existing infrastructure and provides for a seamless integration of new services activation within the confines of the existing OSS/BSS back 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 set optimized for transition management. FASST enables you to manage the multitude of transitions you need to execute in order to differentiate yourself from your competitors through new services and service delivery 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 and the introduction of profitable new managed services. In short, FASST enables Transition without Compromise. For your convenience, a list of acronyms can be found at the end of this document. 1

3 Turning the Vision of IP Video Distribution into Reality FASST is, in essence, our vision for how to transition your network to a service-oriented architecture smoothly 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 be evolved and continuously streamlined. Facing pricing pressures on traditional telephony services, many telecom carriers are being advised to pursue a voice, video and data combination to acquire new residential customers, as well as to avoid the loss of current customers. MSOs are aggressively discounting additional services beyond basic cable and broadband Internet, such as VOD and IP telephony. The mainstream satellite providers are attempting to branch out into data. Meanwhile, the network vendor community and trade press are buzzing over the prospects of cable and telephone companies offering triple play services, regardless of the unfulfilled revenue promises from years past. Fujitsu believes an MPLS-enabled Layer 2 multicast approach addresses the technical requirements, as well as all of the critical business issues impacting the ability of service providers to offer residential broadcast video. In addition, we believe the Fujitsu Reference Architecture, as shown in Figure 1, provides an innovative, differentiable and cost competitive video offering to its subscribers. The following sections set forth the Fujitsu Reference Architecture in comparison to various reference architectures by the DSL Forum and ITU-T. The sections also provide several case studies to support the viability of the Fujitsu approach. TV PC STB V+ Remote Remote VSO Remote 2105 VSO VSO VSO Remote 4100 VSO Gig-E Metro Network 8100 B E VOD Servers VHO LAN Switch BRAS BRAS E I VOD Control Super Head End National IP Network Third Party ISP Internet STB PC TV Figure 1: The Fujitsu Reference Architecture for Video Distribution 2

4 The Fujitsu Reference Architecture for Video Distribution The Fujitsu Reference Architecture uses an MPLS-enabled Layer 2 multicast approach (P2MP LSP), deployed over a carrier-grade Optical EAN. Multicast services are supported over P2MP connections, allowing a connection-oriented approach for the multicast services, in contrast to connectionless forwarding employed 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 a connection-oriented VLAN stacking solution in the access rings, where MPLS is not used. The P2MP LSP can also be established by signaling protocols such as RSVP-TE but is currently established by ASPEN, the element and service provisioning manager of the Reference Architecture. The advantages of using connection-oriented MPLS P2MP connections for video distribution services include: Hard QoS and bandwidth guarantees Since the circuit path is pre-provisioned, CAC mechanisms can be used to reserve bandwidth for multicast circuits along the path in the correct class of service. This process guarantees the bandwidth of the multicast traffic, as well as the bandwidth for other lower priority traffic that may still need hard QoS and bandwidth guarantees. This approach is far superior to the DiffServ approach of relative QoS where multicast traffic may be assigned with EF code-point but would have impact on the traffic not marked with EF. Co-existence with other residential and business services Service co-existence is made possible due 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 sources without any interaction between them. The network automatically switches from one video source to the other upon any unforeseen video source failure so that TV multicast traffic is continuously being transmitted 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 failure is 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 the aggregation of multiple multicast groups onto one connection and forwards all of them according to a single MPLS label rather than separate IP multicast addresses. With this approach you do not have to maintain a state per multicast group in each device on the network, reducing the resources needed for multicast support. In addition, when a failure occurs in the network, you do not need to wait for the convergence of all the different multicast groups to work around the failure. Only the affected multicast groups are switched over to the protection tunnel, along with the P2MP connections that carry these multicast groups. Layer 2 Transparency The P2MP connections allow control protocols for the multicast traffic to be carried transparently inside the connections, without requiring the intermediate nodes to terminate or process them in any way. High security The service provider provisions the P2MP connections and assigns the video source interfaces (i.e., only these interfaces are allowed to connect video sources). This process is very different from IP multicast routing protocols such as PIM in which anyone on the network has the capability to broadcast from a video source. 3

5 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 by the TR-058 specification from the DSL Forum. A key difference between the Fujitsu Reference Architecture and that of the DSL Forum is that some applications can connect directly to the EAN. Examples of such applications are video headends and VOD servers, or video streamers that are located in a local region and insert or piggyback their content with 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 and VSO locations. Dual latency paths and dynamic rate re-partitioning are supported, which is required to support low latency data applications and very low bit error rates for video content. 50 ms protection is supported for Gigabit Ethernet connections from the s. As such, you do not have 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 SIP message 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-play services, including but not limited to Internet access, TV channel distribution, VOD and VoIP. These services have very different attributes and require different levels of QoS, which translates to provisioning requirements around guaranteed bandwidth, bounded delay and jitter and packet loss rate. These services also have different requirements for failure recovery times. The following sections compare the Fujitsu Reference Architecture with the DSL Forum and ITU-T Reference Architectures for Video Distribution. 4

6 Video Delivery Reference Architectures DSL Forum Reference Architecture The widely used reference architecture from the DSL Forum was introduced in the forum s TR-058 specification document and was adopted by the TR-059 specification document, which added further details on QoS support. The architecture is depicted below in Figure 2. Since the aggregation network between the and BRAS (i.e., the so-called Backhaul Network) in the Fujitsu Reference Architecture is Ethernet-based, the ATM-based functionalities defined in TR-058 and TR-059 do not fully translate to an Optical Ethernet deployment. However, by adopting the terms defined in TR-058 and TR-059, such as V interface and BRAS, the Fujitsu Reference Architecture will provide a common framework for the evaluation. ISP1 TE TE TE IP Router TE Customer Premises MODEM Home Gateway First/Last Mile User Access Access Node Ethernet Based IP Access Network Ethernet Level Aggregation BRAS IP Level Aggregation RP RP ISPn IP Core Network Figure 2: DSL Forum TR-059 Reference Architecture 5

7 Referring to the logical service architecture that is defined within TR-058, which is depicted in Figure 3, is also important. We will use the term service control to indicate all the necessary components that control the services, which include service provisioning and network management stations, AAA servers, security policy servers, resource control servers and the SIP servers, and the term applications to indicate all the necessary 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 Ethernet Based DSL Aggregation. The architecture suggested in WT-101 R2 is depicted in Figure 4. Application Communication Conversational Services Service Provisioning Service Communication QoS on Demand Game Service Network/ Element Management Home Network Access Node VOD Service AAA Network Resource Control AAA Settlement Accounting/ Billing BRAS Aggregation Node Access Network Regional Network V ASP Content Security/DRM NSP Backbone Network Figure 3: The Logical Service Architecture of TR-058 6

8 A10-NSP NSP Regional Network Ethernet-based Aggregation Network BRAS ASP Focus of WT-101 RG V Figure 4: The WT-101 R2 Draft Reference Architecture While most of the content of WT-101 R2 focuses on the required changes or enhancements to and BRAS platforms, the draft reference architecture also describes the V interface and the requirement for the C_VLAN to distinguish customers and the S_VLAN to distinguish service types. The VLAN tag associated with each VLAN is called C_TAG and S_TAG, respectively. The WT-101 R2 document mandates that if both VLAN tags are supported, C_TAG is the inner tag and S_TAG is the outer tag in the frames, as shown in Figure 5. Destination MAC Source MAC Ethernet Type S-TAG C-TAG Figure 5: The VLAN Stacking Requirement of WT-101 R2 7

9 The specifications and functionality proposed by Fujitsu constitute a superset of the previously mentioned frameworks in the context of the QoS objectives that a state-of-the-art video distribution network should achieve. In other words, the Fujitsu Reference Architecture can meet a key superset of requirements as defined within TR-058, TR-059 and WT-101 R2. ITU-T Reference Architecture The 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 Ethernet aggregation, which is provided at Layer 2 and corresponds to the EAN set forth within the DSL Forum reference architecture. The second level of aggregation is IP aggregation, which is provided at Layer 3 and corresponds to a regional or national IP network. ISP1 TE TE TE IP Router TE Customer Premises MODEM Home Gateway First/Last Mile User Access Access Node Ethernet Based IP Access Network Ethernet Level Aggregation BRAS IP Level Aggregation RP RP ISPn IP Core Network Figure 6: ITU-T TR.123qos Draft Reference Architecture 8

10 The major objective of this draft architecture is to investigate and define the QoS control mechanisms for an 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 the mechanisms for its Ethernet aggregation from MEF specifications. TR.123.qos also requires two VLAN tags in order to distinguish customers and aggregate traffic of the same attribute (e.g., the type of traffic). This process 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. While this approach looks at first glance to be similar to the WT-101 R2, the meaning of the A_TAG is much broader than that of S_TAG because traffic can be aggregated not only by the type of service but also by other criteria such as the type of subscriber). Figure 7 illustrates the proposed VLAN arrangement. Destination MAC Source MAC Ethernet Type A-TAG C-TAG Figure 7: The VLAN Stacking Arrangement of TR123qos Draft 9

11 Interfaces Together with the proposed network architecture, three new interfaces are introduced. They are the V+ interface between the and the EAN, the E-I interface between the EAN and the IAN, and the E-B interface between the EAN and the BRAS. By this definition, the EAN is able to work with all s and routers/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 by the 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 10

12 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 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 Functionality The Fujitsu Reference Architecture implements a SIP-proxy behavior because it provides more functionality than a straightforward SIP-proxy gateway. A user-configurable option can send all SIP messages to the CPU for forwarding and processing or identify the session control messages (e.g., INVITE, OK, BYE) and forward those 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 to identify specific SIP messages to be sent to the CPU can be avoided, as all SIP messages will be sent to the CPU for proxy processing. In those areas of the network where SIP will be used to both control sessions and also signal in-session activity, (e.g., flipping TV channels), identifying the session control SIP messages may provide better performance. SIP is a very flexible protocol with numerous options. We assume the service provider will decide on a certain policy pertaining to SIP in the network, including which qualifiers must be in which packets and in what order. Such a policy will make identification feasible for implementation inside 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 rather than to drop sessions intelligently when congestion occurs. All sessions, whether voice or video, possess QoS attributes, such as bandwidth requirements and type of session, which can be compared against the available bandwidth on both the ingress and egress links. This process is very similar to the way that any signaling protocol for bandwidth reservation, (e.g., RSVP-TE) is treated. If the available resources are sufficient to accommodate the newly requested session, the CAC database is updated, and the session is allowed. The actual resource reservation is done upon receipt of the OK message from the server, although the 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, a negative response is composed and sent back to the client. 11

13 Other situations occur when SIP packets are sent by one end but do not arrive at the other end. To cope with such situations, the Fujitsu Reference Architecture maintains the status of active sessions and sends messages on behalf of the server or client to reflect the true state of the session to the receiver. This feature is very important, as it helps facilitate the appropriate utilization of resources, as resources are not maintained for inactive state sessions. State awareness is also vital for the proxy implementation to properly use internal resources. For example, the proxy implementation must be able to tell a new message from a re-transmission of an old message. Contrary to legacy SIP proxy implementations, whose main purpose is to enable connectivity, the Fujitsu Reference Architecture proxy has another vital task admission control. Therefore, while other proxies may not be interested in any more messages after the call has been established, the Fujitsu Reference Architecture 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 in order to provide accurate admission control and dynamic rate re-partitioning. National Content (Primary) 8100 VHO Gbps Metro Ring 8100 VSO Remote Terminal Hardened A-2100 Access Device 1 Gbps Access Ring Gig-E (Backup) Local Content 8100 Network Bandwidth Assumptions National Multicast 700Mbps Local Multicast 84Mbps Gig-E SIP to IGMP Transition *National and Local Content Source at VHO Include all Channels. Figure 8: SIP to IGMP Translation Points Fujitsu Reference Architecture 12

14 The Economics of Video Distribution The concept of Internet bypass is quickly becoming the future of video distribution. Tom Wolzien of Bernstein Research coined this term in a research report titled Pipe Dreams: Media's Exploding Capacity, which was released in May Wolzien suggests in Pipe Dreams that in a world of TiVos and Internetconnected TVs, bypassing the traditional MSOs and connecting directly to consumers via the video distribution architectures that are being built by the ILECs, will be economically and technologically feasible for content providers. This point suggests that the content providers will choose ILEC partners who can provide cost-effective video distribution. As such, a video distribution architecture not only must provide video-quality QoS but also 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 a diverse range of content and data services addressing the requirements of multiple markets, including the Enterprise and residential marketplace, from a single footprint allowing a service provider to lower the CAPEX and OPEX cost on a per-subscriber basis and to increase the addressable revenue per dollar of CAPEX and OPEX. This FASST Video Distribution Architecture approach offers a comprehensive suite of solutions that enable a breadth of data services to all of your customers, extending from broadband subscribers in the suburbs to Enterprise customers in Class A office buildings. The architecture must also support a wide range of access interfaces so that customers can connect regardless of fiber availability or geographic location. Each customer interface has to support common Advanced Subscriber Management functions, QoS features, and per-flow accounting, further ensuring the consistency of the user experience and the enforcement of service level agreements. The following sections compare the economics of the Fujitsu Reference Architecture with competing architectures and set forth the appropriate business metrics which service providers should consider in the context of a selection process. 13

15 The FASST Economic Advantage Architectures for Narrowband or Broadcast Services This section focuses on certain baseline architectures designed for telephony or broadcast video service provisioning: HFC, DLC and FTTP. HFC Architecture The HFC architecture employs a combination of both fiber and coaxial cable. HFC employs a fiber backbone that corresponds to the fiber feeder in the DLC and the FTTP networks. HFC can be used to deliver both distributed video and telephone services and can carry up to 500 channels (for a 500 home node, implying one channel per home). In addition, HFC systems can simultaneously support VOD and telephony. For broadcast transmission, HFC provides each subscriber with the same group of video channels, therefore, a high sharing of resources exists. The HFC headend receives signals from local studios, over-the-air broadcasts, 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 to serve the household. The HFC distribution plant consists mainly of coaxial cable. Because of the large attenuation of signals over coaxial cable, feeder amplifiers (mini-bridgers and line extenders) are necessary to amplify the signal for both forward and return paths. Passive equipment includes taps, connectors, 3-way splitters, power inserters and directional couplers. Sixty-volt power supplies drive the active equipment in the distribution network. The drop loop consists of coaxial drop cable. Lastly, an addressable converter is needed on the subscriber 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 Architecture DLC is a fiber-based architecture that is typically used by telephone companies to provide narrowband telephony, like POTS and data services. The DLC system analyzed for this paper utilizes a terminating DSL modems over copper at the customer premises, which is then backhauled to the IOF network utilizing ATM trunks. From a video distribution perspective, a multiservice Layer 3 BRAS router is normally used to provide PIM-SM multicast support and subscriber management. FTTP Architecture An FTTP archtecture is very similar to a DLC system. In an FTTP system, fiber is extended past the node and to the home. This process offers several advantages: first, FTTP exploits the high capacity of fiber by sharing the transmission facilities over more subscribers in the distribution network and second, by deploying more fiber, FTTP lowers the incremental investment needed for broadband services. In an FTTP system, remote electronics, referred to as a host digital terminal, take a high bit rate signal from the CO terminal and demultiplex the signal via a fiber bank assembly onto lower bit rate distribution fibers. 14

16 This architecture is well suited for reliable delivery of video, telephony and data services. A key difference between the HFC and the FTTP architectures is the means used to transport digital signals from the remote terminal to the curb. FTTP uses baseband transport of digital signals over low noise fiber. HFC requires the modulation 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 Models In this section we present an economic comparison of the Fujitsu Reference Architecture with HFC- and FTTP-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 the infrastructures to enable them in their traditional roles of supporting interactive video services. The architectures 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. Assumptions The set of assumptions governing the costs models are outlined below. These assumptions are representative 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 network headend 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 to be 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 broadcast analog services. A digital set-top box, which is needed for all IVS and for enabling the all-fttp network to 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 interactive service penetration rate. IVS offerings are considered to be 70% requiring 1.5 Mbps and 30% requiring 6 Mbps, with a set-top to user ratio of 1.6. This ratio corresponds to an average bandwidth of 2.85 Mbps per IVS channel. Note that this ratio imposes a relatively low demand on bandwidth per channel. Demands on system bandwidth may 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. 15

17 The FTTP architecture used in this analysis represents a custom development carried out by broadband technologies that attempts to optimize either ATM switching technology, routed Ethernet technology or DWDM technology to account for asymmetric bandwidth requirements of IVS in the forward and return directions. Combining video with telecommunications data streams already present on the FTTP networks offers additional optimization. From the viewpoint of cost modeling, assigning costs for a custom developed architecture is difficult unless detailed system designs are available. Hence, our approach has been to estimate the cost of a system providing SDV functionality equivalent to that of the telecommunications services. We treat telecommunications and video services independently, but this assumption is not allowed to affect the cost estimate significantly. This approach is useful in providing a rough estimate of the incremental cost of SDV services over FTTP and, as is shown later, is extremely useful in 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. A 40% markup is also applied to the incremental costs for interactive video services to account for installation costs. 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 considered for 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. 16

18 Results and Economic Comparisons Figure 9 illustrates the combined results for the scenarios outlined in the previous section. Based on these results, 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 Fujitsu Reference Architecture when compared with the HFC/FTTP/DLC infrastructure costs FTTP Routed Ethernet DLC-ATM HFC-Routed Ethernet Fujitsu Reference Architecture FTTP-DWDM Cost Per Home in Dollars % 10% 15% 20% 25% 30% 35% 40% 45% 50% Penetration Rate 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 penetration rates between five and fifty percent, followed by the FTTP-ATM hybrid architecture. Within this same range of penetration rates, the remaining three scenarios have comparable costs. However, we notice that as the take-rate increases, the cost for the remaining scenarios seem to increase at a greater rate than the Fujitsu Reference Architecture (beginning at the 25% penetration rate). We believe this cost differential is based on the operational and provisioning costs incurred as a result of maintaining multiple element management and provisioning systems for optical, routed Ethernet and ATM systems as compared to a single element management and provisioning system for the Fujitsu Reference Architecture. In addition, the utilization of Layer 2 multicast significantly reduces (by as much as 50%) the Gigabit Ethernet ports required to support Layer 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 costs are substantially higher. 17

19 Conclusion The results of this analysis clearly indicate that the Fujitsu Reference Architecture is the most economical approach for provisioning video distribution, particularly at initial penetration rates. We also believe that the Fujitsu Reference Architecture is the best-in-class technical solution, based on the technical advantages which were described earlier in this paper. FASST provides a tremendous amount of solution-level value to you as you face the challenges of how to remain viable and achieve differentiation in this competitive environment. First, Fujitsu is applying its well-respected interoperability and certification processes to its internally developed products, as well as to the alliance partner products, providing you with an extra level of quality and 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 the Fujitsu 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 to raise the bar with best-of-both-worlds solutions that fill gaps as your requirements evolve in step with your end customer demands. Third, while Fujitsu offers competitive and, more often, superior products, our primary advantage is that we understand how to build, manage and operate networks better than any other supplier. We continue to maintain our share in our area of expertise the optical transport industry and our products are deployed in every major carrier in North America. Given this competitive environment, carriers prefer to do business with companies they have had a positive experience with and who they trust companies such as Fujitsu. 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 18

20 Changing customer and application requirements, emerging technologies and the need for new business models 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 define the managed services you can support, as well as your ability to profitably and competitively deploy nextgeneration services. To assist with this transition, Fujitsu has developed FASST, an architecture and solution set optimized for transition management. FASST is relevant to you because it reflects your business objectives. Fujitsu recognizes the drivers that are accelerating the pace of transition. We have responded with a solution that allows you to provide services without boundaries; to provide value-added, network-based managed services; to manage your transition in orderly stages; to streamline your operations; and to decrease your risk. FASST also includes the full experience of Fujitsu, a trusted advisor in telecommunications for more than 20 years. In short, FASST enables Transition without Compromise. 19

21 Acronyms Acronym A_TAG ASPEN ATM BRAS BSS C_TAG CAC CAPEX CO C-VLAN DLC DSCP DSL DNS DWDM EAN EF E-LAN FASST FTTP HDTV HFC Descriptor Aggregation Tag Atrica Service Platform for Ethernet Networks Asynchronous Transfer Mode Broadband Remote Access Server Broadband Switching System Customer Tag Connection Admission Control Capital Expenditures Central Office Customer Virtual Local Area Network Digital Loop Carrier Diffserv Code Point Digital Subscriber Line Digital Subscriber Line Access Multiplexer Domain Naming System Dense Wavelength Division Multiplexing Ethernet Aggregation network Expedited Forwarding Ethernet Local Area Network Flexible Architectur for Subscriber Service Termination Fiber To The Premise High Definition Television Hybrid Fiber Coax 20

22 Acronym IAN IGMP ILEC IOF IP ITU-T IVS MEF MPLS MSO OPEX OSS P2MP LSP PIM-DM PIM-SM POTS QoS RSVP-TE SDV S_LAN SIP VHO VLAN VOD VoIP VSO WDM Descriptor Internet Access Network Internet Group Multicast Protocol Incumbent Local Exchange Carrier InterOffice Facilities Internet Protocol International Telecommunication Union-Telecommunication Integrated Video Services Metro Ethernet Forum Multi Protocol Label Switching Multiple System Operator Operational Expenditures Operational Support System Point-to-Multipoint Label Switch Paths Protocol Independent Multicast-Dense Mode Protocol Independent Multicast-Sparse Mode Plain Old Telephone Service Quality of Service Resource Reservation Protocol-Traffic Engineering (MPLS) Switched Digital Video Service Virtual Local Area Network Session Initiation Protocol Video Headend Office Virtual Local Area Network Video On Demand Voice over IP Video Serving Office Wavelength Division Multiplexer Copyright 2004 Fujitsu Network Communications Inc. All rights reserved. FLASHWAVE and FLASHWAVE (and design) are trademarks of Fujitsu Network Communications Inc. (USA). FUJITSU (and design) and THE POSSIBILITIES ARE INFINITE are trademarks of Fujitsu Limited. All other trademarks are the property of their respective owners. 21