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  1. 1. REDEFINING IPTV WITH THE SUN STREAMING SYSTEM Video-on-Demand (VoD) and Network Personal Video Recording (nPVR) for an Open Systems World White Paper April 2007
  2. 2. Sun Microsystems, Inc. Table of Contents Executive Summary . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Redefining Video over IP . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 Personalized television services . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2 The Sun Streaming System: open, innovative, and scalable . . . . . . . . . . . . . . . . . . . 4 Key Sun Streaming System technology innovations . . . . . . . . . . . . . . . . . . . . . . . . . 6 Sun Streaming System Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9 The Sun Fire X4950 Streaming Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 The Sun Fire X4500 server . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 Sun Fire X64 servers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Network switching and configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17 Sun Streaming Software Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Software components and architecture overview . . . . . . . . . . . . . . . . . . . . . . . . . . 19 Sun Streaming System management . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21 Failure detection and recovery . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23 The Sun Streaming System in Context . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Integrated third-party components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Sun Streaming System interactions with third party components . . . . . . . . . . . . . . 28 Deploying the Sun Streaming System for IPTV . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Video distribution considerations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 The Sun Streaming System in a headend . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Sun Streaming System design example . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Configuring the Sun Streaming System with the Sun Customer Ready Program . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 Conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
  3. 3. Executive Summary Sun Microsystems, Inc. Executive Summary Offering video services over existing IP networks holds considerable promise in terms of new revenue and business growth opportunities for video service providers. Home video in all of its forms is now a large and growing business, and video on demand (VoD), networked personal video recorders (nPVR), and interactive video services can offer considerable convenience and tailored services in an already strong market. Early indications are that a large percentage of broadband customers would subscribe to interactive video services, with considerable potential for growth. This promise is offset by the challenges of designing and deploying scalable, reliable, and cost-effective infrastructure for television services over IP networks (IPTV). Both subscribers and operators expect a highly reliable service and downtime is a threat to customer satisfaction. In addition, since IPTV requires significantly more components than a conventional broadcast video service, it is important that architectures support cost-effective redundancy and failover mechanisms, along with systematic scalability to match growing demand. Unfortunately, traditional disk based video server architectures often lack the scalability needed to address a large customer base with an appetite for a diverse range of video titles. The relatively low number of streams served by individual disk-based servers means that very large numbers of servers and disks must be deployed to serve anticipated growth. These large deployments drive accompanying complexity and server sprawl, and add to networking and system administration cost burden. Complicating matters, many IPTV solutions have proprietary elements that serve to lock organizations into the innovations of a single vendor. The innovative Sun Streaming System overcomes these issues with a solution that meets scalability, cost, and availability requirements with an open and standards based approach. With high-speed memory-based streaming and a significant degree of integration, the Sun Streaming System provides a cost-effective end-to-end solution for centralized interactive television networks capable of supporting the largest and most demanding deployment requirements. This paper describes the challenges faced by video service operators as they deploy IPTV, and also describes the Sun Streaming System components and software architecture. Examples are also provided to illustrate how the Sun Streaming System fits into video services network architecture based on open standards.
  4. 4. 2 Redefining Video over IP Sun Microsystems, Inc. Chapter 1 Redefining Video over IP Consumers of video services are moving away from traditional broadcast models toward services that provide them with more channels and more choice, both in how and what they view. • Personal video recorder (PVR) services and digital video recorder (DVR) devices are becoming common, primarily for time-shifting of regular TV programming, but also for skipping mass-market advertisements that are not targeted to individual consumers. • Video on demand (VoD) is now available in many major cable markets, and the size of content libraries continues to increase. • Broadcast television advertising revenue is flattening in many major cable markets, as advertisers shift spending to more targeted advertising opportunities. These trends are promising indeed for video service operators and others poised to provide flexible digital IP based television services over their broadband networks. Personalized television services The opportunity to deliver personalized video entertainment to each subscriber is significant. Innovative and targeted services promise to capture new customers and aid in retention of those customers for other services. Service providers stand to gain from providing “triple-play” strategies, delivering voice, video, and data to their customer base. The result can be more choice for customers while helping to enable higher revenue streams for service providers. IPTV opportunities Growth in spending on video entertainment in the past few years has coincided with reduced spending on other services such as long-distance and local telephony. While communication and video entertainment services are certainly distinct, this trend may serve service providers by equalizing the revenue opportunities with existing customers. For others, IP networks provide an ideal medium for delivering interactive digital video services. Coupled with existing investments in network infrastructure made over the last 10 years, a significant opportunity exists in delivering on-demand or interactive video and television services using Internet broadband architecture. This opportunity is particularly attractive given new technology advances that are driving down the cost per individual delivered video stream.
  5. 5. 3 Redefining Video over IP Sun Microsystems, Inc. IPTV broadband requirements To be cost-effective, IPTV architecture must leverage existing IP broadband infrastructure. In addition, any proposed architecture must be able to scale, both in the number of streams delivered, and in the basic manageability of the infrastructure involved. IPTV architectures will fail unless they can scale to handle the growth of subscribers and the shift from standard to high-definition TV. IPTV requires a high-bandwidth IP network connected to the home. Fortunately, a number of broadband network topologies are available to deliver IP packets over copper wires (xDSL) or fiber (PON, FTTC, or FTTH topologies). Through these technologies, multiple subscribers are aggregated at the logical level onto higher-speed connections, giving the subscriber a dedicated switched IP packet connection. This aggregation takes place with either virtual circuit multiplexing (Level 1), or via Ethernet switching (Level 2), or IP routing (Level 3). In any of these scenarios, the subscriber is provided with a dedicated, switched IP packet connection. Despite the use of Internet technology, IPTV has requirements that are distinct from a conventional Internet services: • Unlike Internet services, interactive television and video services do not originate from the Internet but rather from the internal network of the video service operator, reducing demands on Internet bandwidth. • Unlike traditional IP based services that can accept some level of packet loss or retransmissions, video services require reliable transmission of packets to the subscriber. Broadband networks must have the necessary bandwidth, and must be engineered to provide the high-quality services that customers demand. • Unlike traditional IP applications, video service traffic is largely unidirectional as it originates from a video server and terminates on a set-top box. The exact bandwidth provisioned per subscriber depends on the encoding of the video stream, the resolution of the video content, and the number of streams supported per household. A data rate of 2 Mbps is sufficient for one H.264/AVC standard definition stream, whereas a high definition stream will require approximately 8 Mbps. Deployment considerations Deployment considerations for IPTV involve whether to select centralized or distributed topologies, or a mixture of both. A centralized headend or video hub office (VHO) with optical transmission streams to locations of broadband distribution is generally lower cost than a distributed video server architecture that replicates content and video streams in multiple locations. The economic trade-off is the cost of transmitting video streams over high-bandwidth fiber versus the cost of replicating and maintaining video servers in remote distribution hubs.
  6. 6. 4 Redefining Video over IP Sun Microsystems, Inc. With the latest optical transmission technology, it is now possible to transmit high bandwidth video over long distances. For example, 80 Gbps video can be sent using coarse wavelength division multiplexing (CWDM) and 320 Gbps video can be sent using dense wavelength division multiplexing (DWDM). As long as fiber is available, there is virtually no limitation to the number of virtual private video streams that can be transmitted from a central location, greatly reducing equipment and operational costs. Since all new generations of last-mile access broadband technologies can handle the necessary data rates per subscriber, the real challenge is in engineering a service delivery platform that can be operated and managed cost-effectively. Most existing video delivery platforms rely on very large numbers of distributed, small-scale video servers — making it difficult to provide a cost-effective and compelling service: • Supporting thousands of geographically distributed servers is an expensive and complex challenge • Distributed, small-scale locations often provide a hostile environment that reduces the reliability of equipment • Distributed resources are difficult to share, leading to resource replication, content replication, and increased cost The Sun Streaming System: open, innovative, and scalable Responding to these challenges and opportunities, the Sun Streaming System represents a truly disruptive solution for service providers who want to increase average revenue by delivering IPTV services to their subscribers. By tightly integrating best-of- breed products from Sun and key third parties, the Sun Streaming System provides a focused and scalable streaming solution with significant advantages, including: • Reducing the cost of deploying and scaling the streaming media platform and therefore reducing capital expenses • Reducing operational expenses for the IP television business through consolidation of equipment and simplification of the network architecture • Reducing both cost and time-to-market for the introduction of new services through the aggressive use of open Internet standards The Sun Streaming System reduces the cost of IP television services to the extent that service providers can aggressively market these new personalized television services to their subscribers to drive large-scale adoption and use. The result can be increased
  7. 7. 5 Redefining Video over IP Sun Microsystems, Inc. bandwidth usage, increased revenue, and greater subscriber loyalty. The Sun Streaming System represents an integrated, flexible, and scalable architecture depicted from a high level in Figure 1. Supervisor node(s) Content Controller node(s) Streaming Software Servers Session Controller node(s) (Sun Fire X4100 servers) Import Pre-Processor node(s) Media Store nodes Sun Fire X4500 server(s) Sun Fire X4950 Streaming Service nodes Streaming Swtich(es) Sun Streaming Software Sun Streaming Hardware Figure 1. High-level block-level diagram of the Sun Streaming System Key benefits of the Sun Streaming System include: • Improved economics The Sun Streaming System offers significantly improved economics for video streaming and content storage. Smaller numbers of high-performance systems and components coupled with a high level of integration of both servers and networking eliminates separate networks and boxes. Sun’s solution also provides considerable consolidation opportunities over traditional video server infrastructure. Management of video services is simplified and secured through role-based access control and authentication. Digital access management and conditional access system (CAS) integration means that providers aren’t loosing revenue through theft. An open-systems approach means that the Sun Streaming System is flexible and integrates well with essential third-party components, easing integration through open interfaces and providing flexibility for service providers to choose best of breed third party components.
  8. 8. 6 Redefining Video over IP Sun Microsystems, Inc. • Scalability in multiple dimensions The Sun Streaming System provides massive scalability that allows operators to deliver high-capacity unicast video services. The Sun Streaming System provides multiple, independent dimensions of scalability, including: – Streaming capacity to serve a very large number of concurrent subscribers with high-quality video – Session management capacity to help ensure large numbers of coexisting con- current sessions, high session setup/teardown rates, and low-latency session control such as processing trick-play events (fast-forward, pause, rewind) – Content import capacity to allow a high number of multicast linear-TV streams and VoD assets to be imported concurrently – Content storage capacity to support a very large number of video titles • Integration and consolidation The Sun Streaming System provides integrated multiplexing, switching, and optical transmission to simplify configurations and even eliminate the cost of switched/routed transmission networks. Key Sun Streaming System technology innovations The Sun Streaming System can be used as a part of an end-to-end solution for centralized interactive television networks capable of supporting the largest and most demanding deployment requirements. The following sections describe the technology innovations that are key to the functionality of the Sun Streaming System. • Memory-based streaming, de-coupled from storage Most conventional video servers are disk based, meaning that they stream video content directly from hard disk storage. Unfortunately, disk access rates have not improved significantly over time, imposing fundamental limitations to this approach. As a result, it is difficult to achieve sustained disk data transfer rates of more than 150 Mbps per disk drive — corresponding to 75 standard definition H.264/AVC streams at a data rate of 2 Mbps. With this performance limit, scaling the number of streams required by a disk- based streaming solution becomes extremely resource- and space-intensive. For example, to achieve 1 million streams would require 25,000 disk drives, assuming that access to these disk drives could be perfectly load balanced. In reality, perfect load balancing is not feasible, further increasing the number of disk drives required. The cost, space, power, and reliability issues associated with such a large number of disk drives make this solution impractical. The Sun Streaming System architecture addresses the disk bandwidth bottleneck by using a large amount of solid-state memory as a cache for frequently accessed content. With up to 1 terabyte (TB) of DRAM memory, the Sun Fire X4950 Streaming Switch can cache up to 1,000 hours of frequently accessed high-quality
  9. 9. 7 Redefining Video over IP Sun Microsystems, Inc. MPEG2 streams. For example, each Sun Fire™ X4950 Streaming Switch shared memory system has sufficient bandwidth to service 80,000 simultaneous 4 Mbps streams or 160,000 2Mbps streams. Within the Sun Streaming System, video content is stored on Sun Fire X4500 servers that provide content storage in increments of 24 terabytes. Each Sun Fire X4500 server provides up to 4,700 hours of high-quality MPEG2 content, including trick-play overhead (indexed fast forward and rewind streams at multiple speeds). Content is automatically moved from Sun Fire X4500 servers into the Sun Fire X4950 Streaming Switch cache based on content access patterns. • Network integration and consolidation In a conventional IP television architecture, banks of video servers connect to the broadband network through a separate switch. This approach can add significant cost and complexity to video server solutions since the switch has to be able to handle large amounts of traffic while minimizing packet loss, latency, and jitter. The Sun Streaming System architecture integrates the video server and video switching function into the Sun Fire X4950 Streaming Switch, greatly simplifying both architecture and implementation. The Sun Fire X4950 Streaming Switch eliminates the need for a separate network switch to cross-connect a large number of video servers, and solves the problems associated with packet loss, latency, and jitter. In addition, even though the Sun Streaming System is comprised of multiple systems and switches, it functions, and is managed as a singular system. • Optical transport integration Conventional IPTV architectures employ separate (active) wavelength division multiplexer (WDM) optical transport equipment, adding to the complexity of typical deployments. In contrast, the Sun Streaming System architecture integrates the WDM laser components directly into the Sun Fire X4950 Streaming Switch, and requires only a passive WDM multiplexer. This level of integration eliminates the need for another separate active component, further reducing cost and increasing reliability. The Sun Streaming System approach is to use a 32 lambda or 40 lambda DWDM optical transport, with one 10 Gbps Ethernet transport per lambda. The Sun Fire X4950 Streaming Switch directly accepts pluggable XFP DWDM and does not require separate optical transport equipment, greatly reducing cost. Inexpensive passive add-on multiplexers are used to add or remove a wavelength from the fiber. Using 40 lambda DWDM, one optical fiber can carry 400 Gbps, or 100,000 MPEG2 streams at 4 Mbps.
  10. 10. 8 Redefining Video over IP Sun Microsystems, Inc. • Scalable session management In a centralized IPTV architecture, a large number of subscribers can be simultaneously active. Achieving acceptable response times requires considerable CPU resources to rapidly respond to subscriber requests. The Sun Streaming System system achieves this level of scalability with multiple high-density network-based Sun Fire servers based on AMD Opteron™ processors. These Sun x64 servers can be scaled independently of other components of the Sun Streaming System to manage concurrent sessions, provide session setup and teardown, and handle session control such as receiving and managing trick-play events (forward, pause, rewind). Individual Sun x64 servers act as Sun Streaming Software nodes. • Network based redundancy High availability is a key concern for any system where failure can affect a large number of customers. One key advantage of the Sun Streaming System is that it can be deployed in an end-to-end redundant architecture, where the failure of any single component will not affect video streaming operation. In a Sun Streaming System configuration, multiple Sun Fire X4950 Streaming Switches, multiple Sun Fire X4500 servers, and multiple Sun x64 servers running Sun Streaming Software can be deployed for scalability and redundancy — resulting in carrier-grade reliability. This approach also helps minimize both planned and unplanned downtime through non-disruptive upgrades and repairs.
  11. 11. 9 Sun Streaming System Architecture Sun Microsystems, Inc. Chapter 2 Sun Streaming System Architecture The Sun Streaming System is not a single product, but rather a collection of hardware, software, and networking products designed to function as a single system. The Sun Streaming System is tested and integrated with third-party asset management software, IPTV middleware software components, and set top boxes (STBs) to help accelerate and simplify IPTV deployment (Figure 2). Head-end or VHO Hub Home Session Middleware Startup Sun Streaming System Asset Sun Streaming Stream Set Top Box Management Software Control Sun FireX4500 Sun Fire X4950 QAM or Video Server Streaming Switch DSLAM Figure 2. Sun Streaming System components integrate with third party asset management and middleware elements to deliver interactive video streams to the home While only individual components are implied by the illustration, Sun Streaming System hardware components can be deployed in multiples to provide scalability and high availability. • Each Sun Fire X4950 Streaming Switch caches popular streams in up to 1 terabytes of DDR1 memory, providing scalability and consolidating network infrastructure. Each switch provides up to 32 10 Gb Ethernet connections, supporting up to 160,000 2 Mbps standard-definition H.264/AVC streams or up to 40,000 8 Mbps high-definition H.264/AVC streams. • Each Sun Fire X4500 server directly interfaces to at least one Sun Fire X4950 Streaming Switch via a 10 Gb Ethernet connection, and provides 24 terabytes of storage for video content. • Multiple Sun x64 servers provide scalability and high-performance resources for a range of management and control functions, interfacing with third-party asset management and middleware components. Overall system management, session control, content control, and import processing functions are provided within Sun Streaming Software. Sun Streaming System components and networking architecture are described in this chapter with Sun Streaming Software open systems architecture covered in Chapter 3.
  12. 12. 10 Sun Streaming System Architecture Sun Microsystems, Inc. The Sun Fire X4900 Streaming Switch The Sun Fire X4900 Streaming Switch represents a key innovation for the Sun Streaming System. Based on industry-standard technology such as DDR1 memory and an X64 based processor, the switch provides cost-effective scalable memory-based streaming. Each Sun Fire X4950 Streaming Switch offers: • Up to 1 TB of DDR1 memory • A 320 Gbps non-blocking cross bar switch (1:1 input/output ratio) • Up to 32 10 Gb Ethernet optical networking ports from wire-speed streaming engines This architecture helps ensure that even when a large number of unique streams are requested, the Sun Fire X4950 Streaming Switch continues to deliver at its committed rates. In addition, innovative switch design provides a variety of benefits, including: • Minimal cost per stream With the Sun Fire X4950 Streaming Switch, the Sun Streaming System effectively de-couples its DRAM based streaming from storage. Coupled with unidirectional video networks, this approach provides for a very low cost per stream. • Simple, cost-effective QoS The Sun Fire X4950 Streaming Switch integrates video buffering and caching in a single switch, with optical transport integration based on industry-standard 10 Gb Ethernet. With a downstream network organized as a simple tree structure, the Sun Fire X4950 Streaming Switch can provide simple, and highly cost-effective quality of service (QoS). • Industry-standard technology The Sun Fire X4950 Streaming Switch is based on industry standard technology such as 10 Gb Ethernet, off-the-shelf DRAM, and an X64 based processor. The Sun Fire X4950 Streaming Switch is provided in a 14 rack-unit (RU) chassis (Figure 3). Figure 3. The Sun Fire X4950 Streaming Switch provides up to 1 TB of memory-based streaming and considerable network consolidation and transport integration with up to 32 10 Gb Ethernet outputs
  13. 13. 11 Sun Streaming System Architecture Sun Microsystems, Inc. Switch architecture The Sun Fire X4950 Streaming Switch is specifically designed to move video data without introducing arbitrary bottlenecks. Each switch provides an integrated cross-bar switching fabric with a non-blocking 320 Gbps switching capacity. This design approach taken is distinct from those that might place a processor or buss in the path of video data. In the Sun Streaming System, video data enters the switch over a 10Gb Ethernet connection directly from a Sun Fire x4500 server. The 10Gb Ethernet ports on the switch feed directly into DRAM where the video data is then available for streaming out to clients. Figure 4 illustrates the functional block-level diagram of the Sun Fire X4950 Streaming Switch. Fans Sun Fire X4950 Streaming Switch Chassis System Mgt. FPGA Mini Boss DRAM ECC DDR ECC DDR PCI FPGA PCI-I Central FPGA FPGA Streaming Data Bridge Memory PCI Controller C2SP Tcvr. Tcvr. Tcvr. Tcvr. Tcvr. Tcvr. Tcvr. PCI Tcvr. Tcvr. Tcvr. Tcvr. Tcvr. INTEL PCI Tcvr. Dual GE Hub Tcvr. Tcvr. Tcvr. PCI ECC DDR FPGA FPGA 10/100 64-bit 16 x 10 Gb Ethernet ports per card Rs232 I/O Intel CPU ECC DDR ECC DDR BIOS Optical Card ECC DDR Line Card (Up to two per chassis) Controller Card (Up to eight per chassis) (One per chassis) Figure 4. Functional block diagram of the Sun Fire X4950 Streaming Switch The Sun Streaming Switch is comprised of the following major components: • Controller Card — The x64 based Controller Card provides operational and management support for the Sun Fire X4950 Streaming Switch. With no local disk drives, the Controller Card boots remotely from the Supervisor node (a specialized Sun x64 server running Sun Streaming Software). The controller card schedules incoming data directly to the Line Cards in DMA mode for maximum throughput. Network interfaces on the Controller Card are used for the Sun Streaming System internal network and for management of the switch. • Line Card — Each Line Card provides four on-board FPGA DDR memory controllers and a total of 64 DDR-1 DIMM slots with 1 GB and 2GB DIMMs supported. With eight Line Cards, a single Sun Fire X4950 Streaming Switch can provide up to 512 DIMM slots in a 14U chassis. One DIMM size is supported for all Line Cards in a switch, and the switch initially supports a maximum of 1 terabyte of memory. The design provides scalability since no streaming data traverses the link to the controller card.
  14. 14. 12 Sun Streaming System Architecture Sun Microsystems, Inc. • Optical Card — Each Optical Card (up to two per switch) provides 16 10 Gb Ethernet interfaces utilizing Broadcom BCM8704 controllers. Each group of four 10 Gb Ethernet ports are directly hard-wired to a single Line Card. Optical Cards are hot-swappable, but no redundancy is provided between cards since their ports are dedicated to individual Line Cards. Switch components and I/O The front view of the Sun Fire X4950 Streaming Switch chassis is illustrated in Figure 5. The following modules insert from the front of the chassis: • A single system Controller Card • Up to eight Line Cards • Three hot-swap power supplies that can be inserted and removed without touching the power cords that connect to connectors in the rear of the chassis Hot-swap power supplies (N+1) System controller card Up to eight line cards (up to 1 terabyte) Figure 5. The system controller card, memory line cards, and hot-swap power supplies are loaded from the front of the Sun Fire X4950 Streaming Switch chassis Figure 6 illustrates the rear view of the Sun Fire X4950 Streaming Switch chassis and the following modules: • Two hot-swap Optical Cards (non-redundant) insert from the rear of the chassis (one shown), together providing support for 32 10 Gb Ethernet ports. • Nine hot swap 120mm fans are accessible from the rear of the chassis. • Three independent power plugs are provided on the rear of the chassis.
  15. 15. 13 Sun Streaming System Architecture Sun Microsystems, Inc. Up to 32 10 Gb Ethernet ports Power plugs 9 hot-swap fans Figure 6. Rear view of Sun Fire X4950 Streaming Switch chassis The Sun Fire X4950 Streaming Switch Controller Card and Line Cards (Figure 7) work together to maximize throughput for video streams: Line Card Controller Card Figure 7. The Sun Fire X4950 Streaming Switch features a modular architecture designed for maximum throughput of video streams The Sun Fire X4500 server In contrast to traditional system and storage architectures, the Sun Fire X4500 server defines a approach that consolidates the server, storage, host bus adapters, switching, and multiple disk arrays onto a single high-density system. In the Sun Streaming System, each Sun Fire X4500 server is specifically configured for use as a video storage appliance. Featuring a 4U form factor, the server provides 24 TB of internal storage
  16. 16. 14 Sun Streaming System Architecture Sun Microsystems, Inc. through 48 hard disk drives in a 3.5-inch disk form factor (Figure 8). As used in the Sun Streaming System, the Sun Fire X4500 server feeds video streams directly to one or more Sun Fire X4950 Streaming Switches. 48 high-performance SATA disk drives Figure 8. In the Sun Streaming System, the Sun Fire X4500 server is configured with 48 disk drives and supplies video streams directly to the Sun Fire X4950 Streaming Switch over a 10 Gb Ethernet link Sun Fire X4500 server features The Sun Fire X4500 server is ideal for integration into the the Sun Streaming System because of its ability to deliver dense, low-cost media storage along with balanced system throughput. In the Sun Streaming System, the Sun Fire X4500 server stores video data from either external decoders or FTP servers, and uploads video data to one or more Sun Fire X4950 Streaming Switches via a 10 Gb Ethernet link. The Sun Fire X4500 server provides a scalable and reliable high-density storage solution for the Sun Streaming System, including: • Minimal cost per gigabyte utilizing SATA II storage and software RAID 5 • 48 3.5-inch SATA-II disks in a 4U chassis, yielding 24 terabytes of video storage • 24 terabytes translates to 4,700 hours of MPEG-2 video @ 4 Mbps including trick play files (4/10/32x forward and reverse, total of seven speeds) • High performance from an industry-standard x64 server based on two AMD Opteron processors with 8 GB of memory • Six individual PCI disk controllers • 10 Gb Ethernet output directly to one or more Sun Fire X4950 Streaming Switches • Redundant, hot-pluggable PSUs, fans, and I/O • Built-in service processor and graphics card
  17. 17. 15 Sun Streaming System Architecture Sun Microsystems, Inc. Sun Fire X4500 server architecture The Sun Fire X4500 server features high-performance server engines with dual-socket, dual-core AMD Opteron processors and high-density storage devices to meet the I/O requirements of video storage. The system also includes an extensive set of enterprise class reliability, availability, and serviceability features that reduce hidden service costs by dramatically simplifying system maintenance. The system features redundant hot-swappable disk drives, redundant, hot-swappable fan modules, and redundant hot-pluggable AC power supplies to help enable increased availability and simplified serviceability. A battery backup unit is also provided to prevent data corruption from power failures. In addition, the Sun Fire X4500 server features remote lights out server management, including remote keyboard, video, mouse, and storage (RKVMS), remote boot, and remote software upgrades using the integrated lights out management (ILOM) service processor. Figure 9 illustrates a high- level block diagram of the Sun Fire X4500 server. ECC DDR SDRAM SATA HDDs (4 slots) Marvell 88SX6081 8-port SATA Ctlr PCI-X INTEL 133MHz 6.4 PCI-X Fw82546 GB/sec Tunnel GB NIC Marvell 1 GB 88SX6081 Ethernet 8-port 1GB/sec PCI-X SATA Ctlr Connectors Tunnel INTEL Fw82546 HT 1 Ghz GB NIC 8 GB/sec PCI-X 133MHz Marvell 88SX6081 8-port 8111 1GHz SATA Ctlr I/OHub 8GB/sec PCI-X Tunnel Marvell Controller Controller SP/VGA USB 2.0 88SX6081 BIOS Serial 8-port Port 1GB/sec SATA Ctlr PCI-X 133MHz Marvell 88SX6081 1 GB/sec PCI-X 8-port Tunnel 6.4 PCI-X SATA Ctlr 133MHz GB/sec PCI-X PCI-X 133MHz Tunnel Marvell 88SX6081 ECC DDR 8-port SATA Ctlr SDRAM (4 slots) Figure 9. Sun Fire X4500 server functional block diagram The Sun Fire X4500 server provides the following architectural features: • Each AMD Opteron processor features an embedded single-channel DDR memory controllers. These controllers provide maximum memory capacity and bandwidth scaling, delivering up to 16 GB of capacity and 12.8 GB/second of aggregated bandwidth with 2 CPUs and eight 2 GB DIMMS. • The AMD Direct Connect Architecture directly connects a variety of system components with HyperTransport links. Processors and AMD PCI-X tunnels are connected with 1 GB/second HyperTransport links delivering 8 GB/second aggregate
  18. 18. 16 Sun Streaming System Architecture Sun Microsystems, Inc. bandwidth per link. Processors are connected to memory using the integrated DDR controller delivering 6.4 GB/second. • Two PCI-X slots deliver high-performance I/O with over 8.5 Gbps of I/O plug-in bandwidth. (A 10 Gb Ethernet Controller is installed in one PCI-X slot). • Two Intel 82546GB Dual Port Gb Ethernet controllers server four Gb Ethernet ports • Six Marvell 88SX6081 SATA II storage controllers connect to 48 high-performance SATA disk drives. • Embedded management and legacy I/O support are also included, offering maximum operational flexibility. Sun Fire X4500 server I/O The back panel of the Sun Fire X4500 server is illustrated in Figure 10. Features accessible from the back of the system include: • Redundant hot-swap power supplies • 10 Gb Ethernet port (on PCI card, not shown) • Graphics port • Network and serial management ports to the ILOM system controller • Four USB ports, two in front and two in the rear of the chassis • Four auto-sensing 10/100/1000 BaseT Ethernet ports (RJ-45) Redundant, hot-swap power supplies 10 Gb Ethernet card (not shown) 4 10/100/1000 BaseT Ethernet pots 2 USB ports Graphics and ILOM card Serial management port Figure 10. Rear view of the Sun Fire X4500 server Storage architecture The Sun Fire X4500 server employs Serial ATA II (SATA II) technology for its 48 internal disk drives. SATA II technology is rapidly approaching other disk drive technologies in the prime storage tier, offering features such as device hot-swap compliance and power management compliance. In particular, unlike technologies such as Fiber Channel Arbitrated Loop (FCAL) and shared SCSI, SATA II’s point-to-point architecture is ideal for serving video streams since it reserves dedicated bandwidth to each attached device.
  19. 19. 17 Sun Streaming System Architecture Sun Microsystems, Inc. As discussed, each Sun Fire X4500 server features six SATA II storage controllers, each utilizing a full PCI-X 133 MHz @1.06 GBps bus. The full complement of 48 hot-pluggable 3.5inch SATA hard disk drives provides a total capacity of 24 terabytes with approximately 2 GB/second disk-to-memory throughput and 1 GB/second disk-to- network throughput. In the Sun Streaming System, Sun Fire X4500 servers boot remotely from a central Supervisor node, reserving all 48 disk drives for storing video streams. Each Sun Fire X4500 server is configured as 12 RAID 5 arrays (3 + 1). This redundancy configuration dictates that 75 percent of the storage capacity is available for video data storage. Sun Fire x64 servers Open and standard Sun Streaming Software provides control elements of the Sun Streaming System in a scalable, fault-tolerant, and distributed fashion. Sun Streaming Software runs on standard Sun x64 servers, including the Sun Fire X4100 server (Figure 11), as well as the Sun Fire X4500 servers and Sun Fire X4950 Streaming Switches that make a Sun Streaming System configuration. Different software nodes that comprise the software architecture are described in Chapter 3. Sun Fire X4200 M2 server Sun Fire X4100 server Figure 11. The Sun Fire X4100 server runs Sun Streaming Software components in addition to Sun Fire X4500 servers and Sun Fire X4950 Streaming Switches Based on powerful AMD Opteron processors, these systems provide high performance, large memory support, and a balanced design to help ensure scalability and performance. The 1U Sun Fire X4100 and X4100 M2 servers support two AMD Opteron processors, up to 32 GB of memory and 2 PCI-X slots. For more technical information on the Sun Fire X4100 server, please visit All components of the Sun Streaming System, including Sun Fire X4100 servers, Sun Fire X4950 Streaming Switches and Sun Fire X4500 servers boot remotely from the Supervisor node, a special-purpose node that is responsible for centralized management and control of the Sun Streaming System. Network switching and configuration Even though it is composed of multiple individual systems, the Sun Streaming System functions as an integral system. The nodes are interconnected using a Gigabit Ethernet switch with two VLANs.
  20. 20. 18 Sun Streaming System Architecture Sun Microsystems, Inc. Two separate VLANs are provided containing separate subnets: • The internal subnet enables network remote booting of all Sun Streaming System servers from the Supervisor node. The internal subnet also carries control and data traffic between the various Sun Streaming Software nodes. • The external subnet carries traffic between the Sun Streaming System and non- streaming back-end servers such as the Content Server, Billing Server, etc. The external subnet also carries control information consisting of real time streaming protocol (RTSP) from the client set top boxes that are connected to the system. The unidirectional streaming network that takes video streams from the Sun Fire X4950 Streaming Switch to the carrier network and on to the set top box is entirely separate from the internal and external Gb Ethernet networks (Figure 12). External Network Sun Streaming System (User Defined: Internal Network Content Servers Billing Servers Set Top Boxes, etc.) Figure 12. The Sun Streaming System is configured with internal and external subnets configured as VLANs, and delivers unidirectional video to set-top boxes
  21. 21. 19 Sun Streaming Software Architecture Sun Microsystems, Inc. Chapter 3 Sun Streaming Software Architecture Beyond serving individual streams, service providers need to be able to scale and expand their IP video services without artificial and arbitrary proprietary limitations. To help ensure interoperability, scalability, and flexibility, the Sun Streaming System employs an open systems approach to both software architecture and management. This approach provides distinct advantages, including: • A single point of control for the entire Sun Streaming System • Integration with key third-party components • Multi-dimensional scalability through replication of Sun Streaming Software components • Failover and recovery through software component redundancy The sections that follow describe key Sun Streaming Software software components along with management and failure recovery highlights. Software components and architecture overview Sun Streaming Software provides the key services that are required to import and transmit video streams, as well as services to manage the system as a single entity. These software nodes can be replicated to add fine-grained scalability for additional capacity of individual functions, and to provide for failover in the case of software or hardware failure. Figure 13 illustrates the principal software components along with the open standard interfaces that they provide. CLI, SNMP, Supervisor Supervisor HTTP node node RTSP Session Controller Session Controller CORBA node node Sun Streaming System CORBA Content Controller Internal Control Network Content Controller XML/HTTP node node FTP or UDP Import Pre-Processor Import Pre-Processor Media Store Media Store Streaming Service Streaming Service MPEG2, H.264 node node TCP/IP node node UDP/IP node node UDP/IP Figure 13. The Sun Streaming System software architecture is based on open-systems protocols Supervisor node The Supervisor node runs on a Sun Fire X4100 server (or two for redundancy) and functions as the central point for monitoring and controlling the entire Sun Streaming System, and also serves as a boot server for all of the other Sun Streaming Software
  22. 22. 20 Sun Streaming Software Architecture Sun Microsystems, Inc. nodes. Disk boot images for all other systems reside and are managed on the Supervisor node. As the centralized operation and control system, the Supervisor node presents the external management interface to the Sun Streaming System, interacting with user interface agents such as the command line interface (CLI) and Web interfaces. Simple Network Management Protocol (SNMP) support is also provided. The Supervisor node coordinates the initialization of the system, monitors the state of other nodes, and relays logging messages. Session Controller nodes One or more Session Controller nodes run on individual Sun Fire X4100 servers. Session Controller nodes manage the establishment of sessions for streaming within the the Sun Streaming System. The Session Controller communicates with the third-party components such as the Session Resource Manager (SRM) and set top boxes (STBs) using the real time streaming protocol (RTSP). The Session Controller also controls the Streaming Service node (described below) when trick-play requests are received from individual set-top boxes. Content Controller nodes Running on one or more Sun Fire X4100 servers, Content Controller nodes allow a third- party asset management system to load and unload VoD or nPVR assets. Prior to allowing the operation, the content controller verifies that sufficient bandwidth exists on an Import Pre-Processor node to begin the import process, and that sufficient disk space remains on a Sun Fire X4500 server (Media Store node) to store the content. Import Pre-Processor nodes One or more Import Pre-Processor nodes (on one or more Sun Fire X4100 servers) process MPEG2 or H.264/AVC video streams before they are stored on a Sun Fire X4500 server (Media Store node). VoD content is imported from FTP servers while nPVR content is imported from encoders. The Import Pre-Processor node generates trick-play files and optimizes the structure of the video for disk I/O and packet transmittals. The fast-forward and rewind speeds of the trick-play files are configurable, and there is no limitation on the number of trick-play speeds that can be configured. Media Store nodes One Media Store node runs on each Sun Fire X4500 server in the Sun Streaming System. This software interface allows access to the considerable storage resources and throughput of the Sun Fire X4500 server. Up to 32 Sun Fire X4500 servers can be deployed in a single Sun Streaming System configuration. Running directly on the Sun
  23. 23. 21 Sun Streaming Software Architecture Sun Microsystems, Inc. Fire X4500 server, the Media Store node manages the scheduling of block reading and writing to and from the RAID disks. Blocks are then transmitted to Streaming Service nodes for streaming. Since Media Store nodes also boot remotely from the Supervisor node over the internal network, no local disks are required for boot and local file system support. As a result, the entire disk capacity of each Sun Fire X4500 server (24 terabytes) is available for storing video content. StreamingService nodes One Streaming Service node runs on each Sun Fire X4950 Streaming Switch. Multiple Streaming Service nodes can be deployed in a given Sun Streaming System configuration. As discussed, the Streaming Service nodes interact with Media Store nodes to fetch the streaming content from storage. The Streaming Service node also manages the Sun Fire X4950 Streaming Switch video cache and schedules packet stream transmission to prevent conflicts in the streaming engine. Streaming Service nodes act upon receiving control commands from Session Controller nodes. Sun Streaming System management Just as the Sun Streaming System is designed to function as single entity, it is likewise managed as a single carrier-grade system. This approach reduces complexity and saves administrative expenses over multiple highly-distributed video server platforms. Specifically, the Sun Streaming System is designed to be managed in a geographically dispersed network from one or more network operation centers (NOCs). The management capabilities of the system enable administrators to: • Detect problems before downtime is experienced • Find root cause problems rapidly when a device fails • Manage the system with a minimum of staff • Collect trending data for performance analysis The Sun Streaming System offers three ways to manage the system: • A full-featured command line interface (CLI) provides configuration management capabilities consistent with other carrier-grade equipment. • SNMP support is provided to help operators manage multiple Sun Streaming Systems from a centralized NOC, and is primarily used for fault and performance management. • An intuitive and easy-to-learn Web interface is also provided (Figure 14).
  24. 24. 22 Sun Streaming Software Architecture Sun Microsystems, Inc. Figure 14. The Sun Streaming System GUI provides remote administrative access from a Web-based interface The command line interface (CLI) offers a convenient method for configuration management, and it allows the entire system to be managed from a single interface. Automation typically required in carrier environments is easily accomplished using the robust CLI. This approach provides a number of advantages, including: • No need to log into different applications or nodes • No need to set configuration files on multiple machines • No need to monitor multiple nodes • The ability to detect and prevent syntax and semantic errors • Control over resource utilization • The ability to gracefully add and remove nodes • Redundancy mechanisms The CLI uses a hierarchical access model, where commands are used to move between the levels with the system prompt identifying the current level. Each level of the hierarchy allows access to different functionality. • The User access mode is the top-level access mode in the hierarchy, allowing execution of all show commands. • Enable mode allows the administrator to access all show commands as well as management configuration commands that do not affect the system configuration. • Configuration mode provides access to all commands and command modes to configure all aspects of the system.
  25. 25. 23 Sun Streaming Software Architecture Sun Microsystems, Inc. Failure detection and recovery The Sun Streaming System provides high availability through replication of individual network components such as Sun Fire X4100 servers, Sun Fire X4500 servers, and the Sun Fire X4950 Streaming Switch itself. In addition, individual Sun Streaming System servers feature redundant components that provide for high availability and the scheduling of downtime for necessary repairs. Figure 15 illustrates a redundant configuration of both Sun Fire X4500 servers and Sun Fire X4950 Streaming Switches, allowing quick recovery in the event of failure. Redundant Sun Fire X4950 Redundant Streaming Switches Sun Fire X4500 Servers Redundant 10/1 GB Ethernet Switches Control Traffic Sun Streaming Software Redundant Sun Fire X4100 Servers Figure 15. High availability Sun Streaming System configurations can be achieved by replicating networked components State and fault management The Sun Streaming Systems allows software services to be added or removed while a system is operational. This flexibility is accomplished by changing the state of individual nodes. All Sun Streaming System nodes have the basic capability to report their state (enabled, disabled, or failed) and all nodes can indicate when a fault has been detected. Operator messages can be directed to a log file, the command line interface (CLI), or information can be communicated via SNMP through traps and other thresholds. Sun Fire X4500 server protection and redundancy With RAID 5 support on each of 12 disk banks, the Sun Fire X4500 server is designed to allow disks to “fail in place”, yielding high availability of video content. At the same time, The highest level of protection results when content is replicated in at least one
  26. 26. 24 Sun Streaming Software Architecture Sun Microsystems, Inc. other Sun Fire X4500 server for failure protection. Redundant Sun Fire X4500 servers protect against all failure cases in either disks, networks, or other individual system components. The Sun Fire X4500 server is designed to protect against disk failure. With individual disk banks covered by RAID software, the Sun Fire X4500 server can handle multiple individual disk failures (one per bank). Once a disk in given bank fails, that bank continues to operate but is placed into “degraded” mode until the disk is replaced and the RAID bank is reconstructed. Two or more disk failures in a given RAID bank constitute failure for the Sun Fire X4500 server, and at that point the content on the MediaStore node is considered invalid. Content must then be made available from another MediaStore node or data must be retrieved from an archival system. Sun Fire X4950 Streaming Switch redundancy Replication of Sun Fire X4950 Streaming Switches is recommended to allow for high availability and seamless failover. In a redundant configuration, both Sun Fire X4950 Streaming Switches listen to updates in promiscuous mode, but an internal attribute determines which switch is set to streaming mode, with the other set to standby mode. Each StreamingService node honors all play requests, but the switch in standby mode has its streaming output disabled. The Supervisor node monitors the health of each StreamingService node. When the Supervisor node determines that one Sun Fire X4950 Streaming Switch or StreamingService node has failed, it changes the state of the backup StreamingService node to Streaming mode and output commences. Because the video segments are already in DRAM on the backup switch, the failover is transparent and no video streams are interrupted. Supervisor node redundancy For high availability, the Supervisor node can also be replicated in a Sun Streaming System configuration. In a system with two Supervisor nodes, one is considered the primary node with the other named as backup. An election protocol ensures that there is only one primary Supervisor node. Supervisor nodes implement monitoring objects to detect when a node has failed and the backup node must become the primary node.
  27. 27. 25 Sun Streaming Software Architecture Sun Microsystems, Inc. Redundancy for other Sun Streaming Software nodes Other Sun Streaming Software nodes can also be replicated, either for capacity purposes, or for high availability. • Each Import Pre-Processor node can import up to 100 Mbps of video. VoD import is considered a non-critical event and a spare available server may be sufficient in case of hardware failure. NPVR import is critical due to the time-critical nature of linear video feeds. The nPVR content import model should be to duplicate content import to survive node failure. • The Content Controller node typically does not need to be rated for high load, and the redundancy scheme should be in line with the VoD or nPVR schemes mentioned above. • The Session Controller is critical for the delivery of video so at least one redundant node should be provided in case of a software or hardware failure. The spare node is treated as a hot standby. Each Session Controller node can handle 2,500 simultaneous session requests per second.
  28. 28. 26 The Sun Streaming System in Context Sun Microsystems, Inc. Chapter 4 The Sun Streaming System in Context By their nature, IPTV deployments can be large and complex, and integration can ultimately be one of the most complex and time-consuming tasks for an organization deploying an IPTV solution. Components from a wide variety of vendors must be made to work together as a part of a unified system that presents a high quality of service to the subscriber. Communications must take place not only between components of the new systems, but with legacy systems such as billing. The Sun Streaming System and its integral hardware and software components work in the context of and end-to-end video delivery system. However, more than just providing a video server component, Sun has committed significant resources to integrate with a variety of third-party hardware and software providers. By supporting open and standard interfaces and testing with key third-party component providers, the Sun Streaming System takes much of the time and complexity out of deploying IPTV services. The result is IPTV infrastructure that can be deployed more quickly, reducing time to service for providers. Integrated third-party components Figure 16 illustrates how the Sun Streaming System fits within an end-to-end video delivery system. This perspective is a representative architecture for illustration purposes only. The Sun Video Streaming System can be deployed in other architectures as well. Legend Billing System/CRM Ad Placement Server Control Interface STB Control Subscriber Management System Video Entitlement Server Offer Server Session Resource Management EPG Ingest Broadcast Content Manager Navigation Server Live TV STB STB STB Asset Manager STB STB STB VoD Content CA System Encoder Encryptor Management Console (HTML) Sun Streaming System Figure 16. The Sun Streaming System in the context of an end-to-end video services infrastructure
  29. 29. 27 The Sun Streaming System in Context Sun Microsystems, Inc. The Sun Streaming System interfaces with a number of third-party components in an end-to-end configuration, including: • Broadcast Content Manager — The Broadcast Content Manager (BCM) collects, formats, and distributes Electronic Program Guide (EPG) information for use in delivering Sun Streaming System nPVR services. • Navigation Server — The Navigation Server coupled with the Navigator client running on the set top box manage the video experience and service to the subscriber. The Navigation Server provides nPVR and VoD data to the Navigator client. • Asset Management System — The Asset Manager is responsible for the full lifecycle management of on-demand content and associated services. The Asset Manager manages content flow, including import, distribution, and delivery. The Asset Manager accepts VoD content packages and manages their provisioning into the Sun Streaming System, distributing content and metadata as appropriate, and providing verification capabilities for imported content. • Subscriber and Session Systems — The Subscriber and Session Systems include the Subscriber Management Server, the Entitlement and Offer Server, and the Session Resource Manager (SRM). The Subscriber Management system enables provisioning, verification, and reporting of customer data, driving the following tasks: – Entitlement verification – Offer up-sell and add-on services by verifying subscriber account information – Accurate reporting of requested services – Providing accurate billing for digital services via interfaces to the Billing Sys- tems. • Electronic Programming Guide — The Electronic Program Guide import capability accepts broadcast schedule information from aggregators and providers, validating it and allowing it to be edited if necessary. Unique identifiers can be assigned to broadcast events for nPVR usage. • Digital Rights Management (DRM) / Conditional Access System (CAS) — The Conditional Access System (CAS) protects access to content by managing access to the keys required to decrypt streamed content. Responsibilities include authentication, key management, key distribution/enablement, database and logging, and certificate authority management. • Billing System/Customer Resource Management (CRM) — Billing System interactions are transparent to the Sun Streaming System, taking place through the Subscriber Management System or Entitlement Server. • Ad Placement Server — The Ad Placement Server identifies ads suitable for inclusion in unicast streaming sessions and coordinates with asset management to maintain an up-to-date inventory of provisioned ads. • Encoders — Encoders enable data/video encryption prior to video transport to the Sun Streaming System system. Video transport is handled by using UDP or FTP. The encrypter may have distinct implementations or operating modes for real-time
  30. 30. 28 The Sun Streaming System in Context Sun Microsystems, Inc. encryption (e.g. for broadcast feeds) and stored-content encryption (e.g. for VoD and advertisement asset import). • Set top boxes — Set top boxes from multiple vendors are supported by the Sun Streaming System. Set top boxes communicate with the Sun Streaming System by receiving streams over UDP/IP and using the real time streaming protocol (RSTP) over TCP/IP for control. For a complete and up-to-date list of the third-party components that work with the Sun Streaming System systems, please see the website at Sun Streaming System interactions with third party components As a part of understanding how the Sun Streaming System fits into video services infrastructure, it is helpful to consider how the system interacts with other key software and hardware components. The sections that follow detail key interactions. To reiterate, this is one possible architectural representation. The Sun Streaming System can work within other architectures as well. Navigation Server: managing the user experience Given the high level of expectations for quality of service from video services customers, the user experience is one of the most important parts of any IPTV system. These components can also be some of the most expensive. Figure 17 illustrates the interaction of the Navigation Server with other key components. VOD Asset metadata Asset (Cablelabs 1.1) Navigate Manager Browse Search Navigation Query Server STB Record, User Profiles, Delete Buy, Get Token, Broadcast Entitlement Record, Delete Content Check EPG Metadata Manager (TVA or Entitlement XML-TV) Server Figure 17. Navigation Server interaction Offering integration with a content Navigation Server is key to Sun’s strategy to evolve content delivery to a complete unicast model. When properly implemented, the Navigation server can help to remove the distinction between broadcast and on- demand content. The Navigation Server interfaces to both kinds of content, making the content available to the applications running on the set top box in a unified manner.
  31. 31. 29 The Sun Streaming System in Context Sun Microsystems, Inc. The set top box runs a multimedia home platform (MHP) software stack, enabling the subscriber to perform a wide variety of actions through application software such as that based on Java™ technology. The integration of the set top box and the Navigation Server support personalizing the subscriber experience, acting as a gateway between the set top box and the Entitlement Server, through which purchasing and authorization are transacted. The Navigation Server is also the component that brings together the data required to implement networked personal video recording (nPVR) functionality. With this capability, record and delete requests from subscribers are communicated to the Broadcast Content Manager which then schedules record and delete actions into the Sun Streaming System. Broadcast Content Manager: control nPVR assets In addition to managing storage and deletion of nPVR content, the Broadcast Content Manager also is responsible for providing the electronic programming guide (EPG) content to the Navigation Server for transmission to the subscriber. The Broadcast Content Manager receives information from the EPG, describing what programs are broadcast when, and uses that information to control recording. It also receives information from the Navigation Server regarding programs that subscribers have already recorded, and can schedule deletion of content that no longer needs to be retained on the system. Figure 18 illustrates the integration of the Broadcast Content Manager with EPG import, the Navigation Server, and the Sun Streaming System Content Controller. EPG Metadata EPG Metadata (TVA or XML-TV) Broadcast (TVA or XML-TV) EPG Navigation Content Ingest Asset/Event Record, Delete Server Manager Identifier Schedule, Delete Content Controller Node Figure 18. Broadcast Content Manager Entitlement Server The Entitlement Server acts as a gatekeeper, interfacing with the billing system to make sure that only purchased and approved content is sent out to the set top box. Subscriber data is obtained from the billing system, and subscriber purchasing data is provided back to the billing system.
  32. 32. 30 The Sun Streaming System in Context Sun Microsystems, Inc. The Entitlement Server participates in two main transactions. Content purchases are initiated by the Navigation Server with the Entitlement server responding with a token once the transaction completes successfully. The Entitlement Server is also involved in playlist resolution, which happens after the purchase, when the subscriber issues a play request for a given video stream (Figure 19). Offer Resolve Playlist Server Subscriber Data, Bill Entitlement Billing Server Ad Placement Resolve Ads Server Check Token, Buy, Get Key Get Playlist Get Token Navigation CA SRM Server Figure 19. Entitlement Server interaction Streaming Streaming is the ultimate result of a successful purchase and/or a successful request to play a stream. The Session Controller node is ultimately the central component in stream control, and it interacts with three components: • The set top box is the originator of requests, and the ultimate consumer of video • The Session Resource Manager (SRM) checks the token and returns the playlist • Streaming Service nodes do the actual streaming out to the set top box If a key is required for encrypted content, the set top box retrieves the key from the Conditional Access System. Figure 20 illustrates the streaming interaction. SRM CA Check Token, Get Playlist Session Controller Get Key RSTP Node Stream Playlist STB Streaming Service UDP: Video Node Figure 20. Streaming interaction between the Sun Streaming System and third-party components
  33. 33. 31 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc. Chapter 5 Deploying the Sun Streaming System for IPTV Unlike traditional video servers, the Sun Streaming System can take direct advantage of existing dark fiber for unidirectional video delivery. By facilitating consolidated (rather than broadly distributed) video distribution, the Sun Streaming System can simplify infrastructure, and lower costs while enhancing reliability for video stream delivery. The sections that follow describe the Sun Streaming System in the context of physical network infrastructure, and also provide an example configuration. Video distribution considerations One of the key questions in deploying IPTV infrastructure is whether to provide consolidated or unconsolidated video services, or indeed a hybrid implementation that combines the two. These choices present a number of trade-offs. • Unconsolidated video distribution For small markets with minimal initial demand, unconsolidated video distribution may seem attractive. This approach places video server systems close to the edge of the network, lowers initial costs for small deployments, and minimizes traffic over the backbone network while not depending on fiber availability between the core and the edge of the network. Unfortunately, this distribution scheme means that content is duplicated in a greater number of sites. In addition, both capital and operational expenses increase more rapidly as the number of subscribers increase. An unconsolidated approach also requires more staff and more spare parts over the project lifetime, and those resources are typically distributed over a larger geographic area. • Consolidated video distribution The availability of dark fiber in many networks makes consolidated video distribution an attractive proposition for many service providers. With the Sun Streaming System able to provide massive multi-dimensional scalability, a consolidated approach is considerably more feasible. A consolidated approach leverages the point-to-multipoint flow of video traffic implicit in most network implementations and provides the lowest capital and operational expenses over the lifetime of the project. With video head-end functions managed centrally, a consolidated approach also requires the lowest number of staff for ongoing operations and the lowest number of spare parts. A consolidated and centralized approach can also provide higher reliability by having fewer components that can fail. Having a smaller number of centralized video servers also makes it easier to deploy new services such as nPVR. For example, the even if 100 subscribers record the same show or movie, a centralized Sun Streaming System would only need to store a single copy of the video.
  34. 34. 32 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc. Components of the Sun Streaming System may be appropriate in a range of consolidated, unconsolidated, and hybrid configurations. Given the strengths and scalability of the Sun Streaming System, this discussion will focus on consolidated infrastructure. The Sun Streaming System in a headend or video hub office Figure 21 illustrates the Sun Streaming System components deployed in a headend or Video Hub Office (VHO) as a part of a consolidated distribution network. Figure 21. The Sun Streaming System components in a centralized headend context The illustration is annotated as follows: 1. Multiple Sun x64 servers act as Sun Streaming Software nodes. Each server has a gigabit Ethernet port for internal VLAN communication within the Sun Streaming System, and a gigabit Ethernet port attached to the external network. 2. Multiple Sun Fire X4500 servers can be deployed as a part of the Sun Streaming System. Content is imported from the Sun Fire X4100 servers. Video is then fed to a Sun Fire X4950 Streaming Switch from an integrated 10 Gb Ethernet connection between the Sun Fire X4500 server and the switch. 3. Each Sun Fire X4950 Streaming Switch has 32 10 Gb Ethernet ports, letting it trans- mit up to 80,000 streams at 4 Mbps. Sun Fire X4950 Streaming Switches include integrated XFP modules capable of transmitting up to 40 km over fiber. 4. An optional passive optical multiplexer can be used to combine multiple wave- lengths over a single fiber. 5. The Sun Streaming System leverages fiber infrastructure. Traffic can be transmit- ted on dark fiber, or terminated on a CWDM or DWDM multiplexer.
  35. 35. 33 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc. 6. In the central office, another passive optical multiplexer can be used to demulti- plex wavelengths and terminate them on 10 Gb Ethernet switches. 7. Low cost 10 Gb Ethernet to 1 Gb Ethernet switches are available for terminating video streams. These switches usually have QoS capabilities, and appropriate prior- ities can be assigned to VoIP and video traffic. 8. Video traffic is transparent to edge routers. Routers use QoS functionality to give priority to VoIP traffic. 9. A VoIP gateway connects to a distribution router and sends packetized voice traffic to the legacy voice network. This activity is invisible to the Sun Streaming System. 10. A DSLAM or QAM is located either in the central office or in a remote location. Mul- tiple 1 Gb Ethernet ports are trunked together for uplink to the switch. Sun Streaming System design example Full scoping, design, and sizing of the Sun Streaming System is beyond the scope of this document. However, it is helpful to work through an example to understand some rough criteria for the Sun Streaming System design. This process involves: • Understanding and forecasting relevant key objectives • Translating these objectives into storage and streaming requirements • Designing a system to meet those requirements Collecting key information Designing a Sun Streaming System configuration system involves collecting key data and answering questions about the types and quantities of video data that are anticipated. Key questions include: • At what bit rate will standard definition (SD) and high definition (HD) video be encoded? • How many hours of SD and HD content needs to be stored for VoD? • What is the total number of subscribers? • How many of them are expected to concurrently watch VoD? • How many linear TV channels will be imported for nPVR? Case study: a hypothetical VoD and nPVR system For the purposes of example, Table 1 includes three years of projected data for a video system to serve both standard definition and high definition streams to both VoD and nPVR customers.
  36. 36. 34 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc. Table 1. Requirements over three years for a hypothetical VoD and nPVR system Assumptions Year 1 Year 2 Year 3 Standard definition bit rate 2 Mb/s 2 Mb/s 2 Mb/s High definition bit rate 8 Mb/s 8 Mb/s 8 Mb/s Hours of SD VoD content 2,000 4,000 6,000 Hours of HD VoD content 1,000 2,000 3,000 Total subscribers 10,000 20,000 30,000 Peak concurrent VoD viewers (%) 10% 10% 10% Percent of SD set top boxes 50% 50% 50% Percent of HD set top boxes 50% 50% 50% Simultaneous VoD import (titles) 1 1 1 Linear TV channels (SD) 100 100 100 Linear TV channels (HD) 20 30 40 nPVR subscription rate 30% 35% 40% Peak concurrent nPVR viewers (%) 50% 50% 50% Mean nPVR storage used per subscriber 20 30 40 Simultaneous session and trick-pay 10% 10% 10% requests (% subs per second) Table 2 provides a synthesis of these requirements Table 2. Requirements synthesis for hypothetical system, years 1-3 Requirements Year 1 Year 2 Year 3 Peak concurrent VoD viewers 1,000 2,000 3,000 nPVR subscribers 3,000 7,000 12,000 Peak concurrent nPVR viewers 1,500 3,500 6,000 Peak VoD streaming requirement 5 Gbps 10 Gbps 15 Gbps Peak nPVR streaming requirement 8 Gbps 18 Gbps 30 Gbps VoD + nPVR streaming requirement 13 Gbps 28 Gbps 45 Gbps VoD storage requirements 11 terabytes 22 terabytes 32 terabytes nPVR storage requirements 120 terabytes 420 terabytes 960 terabytes VoD + nPVR storage requirements 131 terabytes 442 terabytes 992 terabytes Peak import capacity 368 Gbps 448 Gbps 528 Gbps Storage overhead estimate (x multiplier) 2 2 2 Session setup/teardown/trick-play 250 per second 550 per second 900 per second Capacity analysis The requirements expressed in the tables above provide sufficient information to build a Sun Streaming System configuration. Only the first year will be considered in this analysis but additional Sun Streaming System components can be easily added as forecast, or as demand dictates. Organizations can choose to deploy redundant
  37. 37. 35 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc. components for greater availability and failover. Both non-redundant and redundant numbers are provided in the sections below. • Storage requirements In year 1, the combination of VoD plus nPVR storage is expected to require 131 terabytes. With each Sun Fire X4500 server supporting 24 terabytes, this requirement translates to: – Non-redundant: six Sun Fire X4500 servers – Redundant: 12 Sun Fire X4500 servers • Streaming capacity The analysis fixed the streaming capacity for VoD plus nPVR streams at 13 Gbps. Each line card has 40 Gbps of streaming capacity so a single line card should suffice to serve the necessary capacity. However, the redundant storage requirements described above require 12 10 Gb Ethernet connections for connecting to Sun Fire X4500 servers. In addition, Line Cards are provided only in increments of 1, 2, 4, or 8. Therefore the Sun Fire X4950 Streaming Switch requirements are: – Non-redundant: One Sun Fire X4950 Streaming Switch chassis, four Line Cards, one Optical Card, one Controller Card – Redundant: Two Sun Fire X4950 Streaming Switch chassis, eight Line Cards, two Optical Cards, and one Controller Card • Import capacity The peak import capacity requirement for this example is 368 Gbps. Since each ImportProcessor node can handle 100 Gbps, the requirements are: – Non-redundant: Four Input Pre-Processor nodes – Redundant: Eight Input Pre-Processor nodes • Other Sun Streaming Software nodes Other Sun Streaming Software nodes need only be provided in singular quantities unless a dual-redundant configuration is desired for availability: – Non-redundant: One Supervisor node, one Content Controller node, one Session Controller node – Redundant: Two Supervisor nodes, two Content Controller nodes, two Session Controller nodes
  38. 38. 36 Deploying the Sun Streaming System for IPTV Sun Microsystems, Inc. Figure 22 graphically illustrates the results of the year-1 analysis. These Sun Streaming System components could easily be accommodated in three 42U racks. 20-30 Gb/Fast Ethernet Access Switches STB STB STB 2 Sun Fire X4950 2-16 10/1 GB Streaming Switches Ethernet 12 Sun Fire X4500 Switches STB STB STB Servers STB STB STB STB STB STB STB STB STB STB STB STB Control Traffic STB STB STB Sun Streaming STB STB STB Software 14 Sun Fire X4100 Servers Figure 22. Logical block diagram of hypothetical VoD and nPVR configuration for year one of the analysis A further projection of the the Sun Streaming System components required for the first three years is provided in Table 3. Table 3. Sun Streaming System components for a hypothetical 3-year VoD and nPVR deployment System Components Year 1 Year 2 Year 3 Sun Fire X4500 servers with 12 38 84 48 500 GB drives Sun Fire X4950 Streaming Switch 2 4 6 chassis with one Controller Card Line Cards 8 20 96 Optical Cards 2 6 12 Supervisor nodes 2 4 6 Import Pre-Processor nodes 8 10 12 Content Controller nodes 2 2 2 Session Controller nodes 2 2 2