Chap 2: Delivery Network Technologies

Learning Objectives  After completing this learning object, you should be able to:  Describe the various next generation networking technologies used to deliver IPTV.  Understand the technical differences between Internet TV and IPTV.  Describe core IPTV network technologies  Define important considerations when designing or upgrading a network to support IPTV.

Module Topics ‘Last Mile’ Technologies Backbone Technologies

 ‘Last Mile’ Technologies  FTTx  xDSL  HFC  Satellite?  The Internet!  Wirelessly NGN

 Bandwidth Requirements Triple Play ServiceTypical Capacity Broadcast-quality MPEG-2 standard-definition (SD) video Between 3 and 4 Mbps MPEG-2 high-definition (HD) television Between 10 and 20 Mbps H.264/AVC compressed high- definition (HD) television Between 6 and 8 Mbps Broadband2 Mbps VoIP160 Kbps Traditional broadcasting is very inefficient: all channels are transmitted to all subscriber locations, although each subscriber only views a small number of channels during a typical day’s TV viewing. In an IPTV network, a multicast program is sent to only those IPTVCDs that have requested to view a channel. This results in huge bandwidth savings!

 IPTV over FTTx  Main Drivers for Fiber in recent years  More bandwidth demands  Lower deployment & equipment costs  Ideal for IPTV

Example PON Technical Architecture Wavelength division multiplexers (Creates Multiple Channels/Wavelengths)

 IPTV over DSL Overview  Short for Asymmetric Digital Subscriber Line  Point-to-point – No bandwidth sharing  8 Mbps downstream & 2 Mbps upstream  2 MPEG-2 SD broadcast TV channels & Broadband  Video delivery via networks built with legacy DSL technologies  Limited to homes within 18,000 Feet of CO  Evolution to ADSL2, VDSL

ADSL Equipment Divides the incoming signal into low frequencies to (telephone) and high frequencies (home) network. Digital Subscriber Line Access Multiplexer Aggregates IPTV subscriber connections Interfaces with core network Connects via USB or Ethernet Often includes router functionality

 IPTV over a Cable TV Network DOCSIS 3.0: data over cable service interface specifications  HFC defines a network configuration of fiber-optic and coaxial cable  Capable of simultaneously transmitting analog and digital services  “Pay as you go" architecture matching investment with new revenue streams  Operates at Gbps

 Wireless IPTV  Using Fixed WiMAX for Delivering Video  Mobile WiMAX and IPTV  Wireless Municipal Networks & IPTV  3G & 4G IPTV

Using Fixed WiMAX for Delivering Video  WiMAX, short for Worldwide Interoperability for Microwave Access is defined in IEEE d.  A high-capacity IP broadband wireless technology – Close ‘relative’ of WiFi.  Promoted & Developed by the WiMAX Forum.  Network architecture:  WiMAX Base Stations  WiMAX Subscriber Units

Mobile WiMAX and IPTV  Features conducive to IPTV Delivery:  Peak data speeds of around 32 to 46 Mbps – facilitates delivery of IP based video content to mobile devices.  It inter-operates with IP Multimedia Subsystem – an architectural framework for delivering IP services to mobile devices.  Mobile WiMAX support s advanced quality of services (QoS) mechanisms – requirement for IPTV services.

Wireless Municipal Networks & IPTV  Municipal Mesh Networks are deployed in cities across the globe  Operate in an outdoor environment in either the unlicensed 2.4 GHz or 5 GHz spectrum range  Wi-Fi is the technology of choice  Constructing muni- networks require access points interconnected to each other and to a broadband connection

3G & 4G IPTV 3G technologies such as EV-DO and HSDPA also support mobile IPTV applications EV-DO  Short for Evolution-Data Optimized  Maximum data rate of 4.9 Mbits/sec HSDPA  Short for High-Speed Downlink Packet Access  Supports rates up to approximately 14 Mbps Provide network operators with the ability to deliver IPTV to areas that are poorly served by DSL and Cable broadband systems

 IPTV over the Internet  Streaming Live channels over the Internet  Internet Downloads  P2P Video Sharing and Social Networking

 Streaming Live channels over the Internet: Technical Architecture  Streaming server functions:  Storing & retrieving source video content  Controlling rate at which the IP video packets are delivered to the client viewing device  Executing forward & back commands as requested by the Internet TV viewer  Multiple servers required for large Internet TV deployments

 Differences between IPTV and Internet TV IPTVInternet TV Networking Platform Leverages the public InternetUses secure dedicated private delivery networks Geographical Reach Located in fixed geographical areas No geographical limitations Control over Delivery Mechanisms The network is owned by the service provider. Thus the network can be engineered to maximise QoE for IPTV end-users. IP packets can get delayed or lost whilst traversing the Internet; resulting in a degradation of QoE for end-users. Delivery is done in a “best effort” fashion. Access Mechanism Typically an IP set-top box combined with a residential gateway. Nearly always a PC. CostsPrimarily free of charge.Monthly subscription model. ContentUser generated & niche channels. This is changing! Traditional television shows and movies supplied by established media companies.

 P2P Video Sharing and Social Networking  Allows users to watch, share, and create online video content  Involves downloading & installing specialized software  Once an end-user clicks on a link, two processes happen:  P2P video sharing application software establishes connections  Retrieve requested video content from a variety of different sources  Viewing can commence once file is downloaded  The PC can then act as a source for other P2P requests

 IPTV Backbone Technologies  Core Networking Technology Overview  ATM and SONET/SDH  IP and MPLS  Metro Ethernet

 Core Networking Technology Overview  Core required to carry large volumes of video, data & audio content  Requirements include:  Multi-path resilience  Link protection capabilities  Very high reliability levels  Core provides connectivity between IPTV data center & ‘last mile’ access networks

 ATM and SONET/SDH  ATM:  A protocol that operates over various network media  Ideal for real-time applications (IPTV)  Synchronous Optical Network (SONET)  Physical layer protocol  High speed transmission over fiber networks  Called Synchronous Digital Hierarchy (SDH) outside US  Data rate is measured by optical carrier (OC) standards  Time division multiplexing (TDM) OC levelSignal Transmission Rate OC-1 (base rate) Mbps OC Mbps OC Mbps OC Gbps OC Gbps OC Gbps OC Gbps OC Gbps

 IP & MPLS: Overview  Large telecommunication are deploying IP at the core.  IP drawbacks:  Limited QoS capabilities  Traffic segregation capabilities  Works well when combined Multiprotocol Label Switching (MPLS)

 IP & MPLS: LSRs  Virtual paths called Label Switched Paths (LSPs) ensure smooth transition of IPTV traffic through the MPLS network  LSPs speed up routing because deep packet inspection only occurs at the ingress and not on each hop  While IPTV packets traverse across MPLS enabled routers a number of local tables called Label Information Bases (LIBs) are consulted to determine details about the next hop along the route.

 Metro Ethernet: Technical  Operate at speeds up to 100 Gbps across long geographical distances  Implements a sophisticated recovery mechanism in the event of a network link failure  Uses Ethernet Virtual Connections (EVCs) to guarantee the delivery of high-quality video content within the network core