Hybrid Coax/PLC Video Distribution Home Networks This paper discusses home networks that can deliver video as well as data and their growing sophistication and capacity. Hybrid networks are based on existing electrical wiring and existing coax wiring. The advantages of such a network include ease of installation, ease of use and lower cost than other (especially custom installed) solutions. In addition, it offers the high capacity needed to transfer SD and HD video. Introduction Internet Protocol Television () is a rapidly maturing technology for the delivery of broadcast TV and other media-rich services over a secure, end-to-end operator-managed broadband IP data network. broadly encompasses rich functionality that ranges from the acquisition, encoding and decoding, access control and management of video content, to the delivery of digital TV, movies on demand, viewing of stored programming, personalized program guides, and a host of interactive and multimedia services. is distinctly different from Internet Video that simply allows users to watch videos, like movie previews and web-cams, over the Internet in a best effort fashion with no end-to-end service management and quality of service considerations. Page 1 of 8
technology, integrated with the higher speed digital subscriber line (DSL) access technologies (ADSL2, ADSL2+ and VDSL), offers attractive revenue-generating opportunities for the telecom service providers, enabling them to compete effectively in the triple play market space with delivery of voice, data and video services to residential and business customers. This paper provides an overview of system architecture and identifies some near-term applications that may be supported by telecom service providers. In addition, the paper addresses generic requirements for customer home networks to support applications System Overview Figure 1 illustrates a generic system architecture that supports applications such as digital (broadcast) television and Video on Demand (VoD). This architecture is based on the comprehensive architecture and services model specified in ITU Recommendation H.610 and on the platform offered by industry leaders. The generic architecture is utilized in this paper as a baseline reference to discuss distribution in-home networks. Content Sources - Content Sources represents functionality that receives video content from producers and other sources, encodes the content and, for VoD, stores content in an acquisition database. Service Nodes - Service Nodes represent functionality that receives video streams in various formats, then reformats and encapsulates them for transmission with appropriate Quality of Service (QoS) indications to the wide-area network for delivery to customers. Service Nodes communicate with Customer Premises Equipment (CPE) for service management and with service for the subscriber, session and digital rights management. Service Nodes may be centralized or distributed in a metro area (e.g. at central offices). Wide Area Distribution Networks Provides distribution capability, capacity, quality of service and other capabilities, such as multicast, necessary for reliable and timely distribution of Page 2 of 8
data streams from Service Nodes to Customer Premises. The Core and Access Networks include the optical distribution backbone network and the various Digital Subscriber Line Access Multiplexers (DSLAMs) located at the central office or remote distribution points. Customer Access Links - Customer delivery of is provided over the existing loop plant and phone lines to homes using higher-speed DSL technologies such as ADSL2+ and VDSL. The distance limitations and bandwidths attainable for these DSL technologies are summarized in Table 1. Service providers may use a combination of Fiber-to-the Curb (FTTC) and DSL technologies or implement direct Fiber-to-the-Home (FTTH) access depending on the richness of their service offerings. Customer Premises Equipment (CPE) - In the context, the CPE device located at the customer premise provides broadband network termination (B-NT) functionality at a minimum, and may include other integrated functions such as routing gateway, set-top box and home networking capabilities. Client - The Client is the functional unit which terminates traffic at the customer premises. This is a device, such as a set-top box, that performs functional processing, which includes setting up the connection and QoS with the Service Node, decoding video streams, channel change functionality, user display control, and connections to user appliances such as a standard-definition TV or HDTV monitors. Page 3 of 8
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Home Applications and Services Digital Broadcast TV - Conventional digital television is delivered to subscribers via an upgraded cable TV plant or satellite systems. The advent of higher-speed DSL technology such as ADSL2, ADSL2+ and VDSL, enables as a compelling and competitive alternative. is currently in testing or planning stages with a number of telecom service providers in North America, Europe and Asia. has the potential to offer services that go beyond what traditional broadcast, cable, and satellite TV providers have offered to subscribers in the past. enables more content variety with a larger number of channels. This makes possible the availability of very diverse content to serve the interests of mass markets, specialized groups and demographic communities. Unlike conventional broadcast, cable and satellite TV, where all channels are simultaneously delivered (i.e. broadcast) to the subscriber home, only delivers those channels which are being viewed by the subscriber and has potential to offer a practically unlimited number of channels. Combined with two-way interactive capability, which is inherent in because of its association with IP, consumers will be able to control what they want to watch and when. A robust internal network will enable, subscribers to extend the experience throughout the home or business. Video on Demand (VoD) The video-on-demand application provides individual subscribers the ability to select video content and view it at their convenience. This enables the service provider to offer additional revenue-generating services, such as: Movies on demand, which the user would select from a movie library available at the Service Node Stored programming content, such as sports events, television shows and newscasts, which can be viewed at a later time. Unlike traditional cable/satellite pay-per-view services where a limited number of movies are broadcast on fixed time-slots, /VoD service would give users more choices and flexibility to watch movies anytime at their convenience. Other compelling applications and potential revenue-generating services, which can be enabled once initial infrastructure is in place, are: Video telephony and video conferencing Remote education Home security/monitoring cameras Page 5 of 8
infrastructure and powerline communications technology bring digital TV, VoD, Internet access, media serving and many other services together for easy access throughout the home. Home Distribution Scenarios Generic Distribution Model for Customer Premises, showing various interfaces per ITU Full Service VDSL Model. Page 6 of 8
The analog Plain Old Telephone Service (POTS) signal is removed from the xdsl signal at the POTS splitter to preserve existing telephone service on home phone lines. xdsl Termination processing includes the xdsl modem and may include additional integrated functions such as a routing gateway to support broadband Internet service. No Traffic on Home Network set-top box functionality and associated Client, is integrated, or co-located, into the same box as the xdsl Termination Processing unit (xdsl modem). Customer-side interfaces on this unit can be Ethernet port for Internet service, VOIPbased analog voice port, and connections to standard TV. In this scenario, traffic does not traverse the home network. Integrated xdsl Termination Processing (xdsl modem) and Set Top Box ( Client). -enabled Home Network xdsl modem and set top box functionality are not integrated as one box. In such cases, video streams are delivered from the xdsl modem to the settop box or TV monitor with an embedded client, over the home network. Home Network Using Distributed Set top Boxes and/or Client-enables Appliances. Page 7 of 8
Pictorial of the Powerline Network Used for Distribution Ethernet-enabled set-top boxes and Ethernet/PLC bridges make this possible. Digital Media Server/PVR Added - an emerging class of home entertainment devices with built-in storage, similar to TiVo, Personal Video Recorders (PVRs) and PCs with large storage for multimedia content. This functionality may be standalone or integrated into a set-top box. Home network bandwidth requirements increase when a shared PVR is used for example, when a user is recording one channel while watching another, the video stream being recorded first goes from the GW to the user s STB and then to the STB with the shared PVR, resulting in two instances of the same stream on the home network. Distribution at Customer Premises showing a local Digital Media Server/ Shared PVR. To learn more about BLUEBIRD TV products and services, please visit or contact us at: info@bluebirdtv.com Page 8 of 8