- ims based iptv infrastructure - antonis hontzeas
IPTV is defined by ITU as “multimedia services such as television/video/audio/text/graphics/data delivered over IP based networks managed to provide the required level of quality of service and experience, security, interactivity and reliability."
IPTV Services are supported by the following functional infrastructure:
IPTV Headend
The IPTV headend accumulates content from a variety of sources such as video, cable, terrestrial, and satellite channels. The content is then processed and prepared for delivery over the IP network. Subscriber profiles (referred to as IPTV subscribers) and payments are managed through a subscriber management system.
Broadband Delivery Network
The delivery of IPTV services require a one-to-one connection. This means that for large deployments, i.e. a large subscriber base, traffic engineering and bandwidth requirements may become quite a challenge especially over traditional copper infrastructure.
Advancements in transmission infrastructure such as fiber based telecommunication networks are particularly suited to the delivery of IPTV content.
Set Top Boxes
Set Top Boxes are key components in allowing people to access IPTV services. The Set Top Box which can usually be found on top of a TV set is responsible for the received video stream processing and general connection of the user device to the broadband network.
Set Top boxes being key IPTV network interfaces also shield the user device from network irregularities and fluctuations.
A Home Network
A home network connects a number of digital devices within a small geographical area. It improves communication and allows the sharing of expensive digital resources among members of a family.
The purpose of a home network is to provide access to information, such as voice, audio, data, and entertainment, between different digital devices all around the house.
With home networking, consumers can save money and time because peripherals such as printers and scanners, as well as broadband Internet connections, can be easily shared.
The Role of IMS ( IP Multimedia Subsystem)
IPTV is based on internet connectivity implying that the services and related technology can be interfaced with other subsystems such as the IP Multimedia Subsystem.
This connectivity offered only by IP technology will allow telecom operators to combine, coordinate, synchronize, mix and match a host of other service suites with the offered IPTV service, thus presenting their subscriber base with an upgradable and evolving cost controlled competitive service bundle.
An IMS-based TV solution contains all of the components normally found in an IPTV solution, such as a head-end system, middleware, media servers, Digital or Conditional Digital Rights Management System, STBs and an infrastructure with IPTV support. The solution relies on an IMS core nodes such as CSCF, HSS and SBG (Session Border Gateway) and related IMS enablers.
IMS and IPTV Middleware
The IPTV middleware relies on SIP signaling over the IMS Service Control (ISC) interface. Such support allows the IPTV middleware to interact with the CSCF node to set up SIP sessions as well as RTSP (Real Time Streaming Protocol) sessions, which control on-demand media streams from the media servers.
The IPTV middleware acts as an IMS application server on top of the IMS infrastructure.
IMS and STBs
In the home network, the STBs need to have an IMS client to communicate with the middleware via SIP and RTSP. Alternatively, a residential gateway with an IMS termination function can be introduced. Such a gateway eliminates the need for IMS support in the STBs. A residential gateway connected to the home network also allows for IMS-controlled services on devices such as PCs, phones and game consoles.
IMS, IPTV and 3GPP
Following 3GPP standards, coming generations of mobile terminals will host native Java-based IMS clients. Integration with IMS-based IPTV, together with IMS supported mobile terminals, will provide the possibility to transfer ongoing TV sessions from the TV in the home to a mobile device and vice versa, without any delay.
Further Reading
For further information, the reader is referred to Torbjörn Cagenius, Andreas Fasbender, Johan Hjelm, Uwe Horn, Ignacio Más Ivars and Niclas Selberg Evolving the TV Exprience (Ericsson Review No.3, 2006) and Peter Arberg, Torbjorn Cagenius,Olle Tidblad, Mats Ullerstig and Phil Winterbottom Network Infrastructure for IPTV (Ericsson Review No.3, 2007).
Both sources were used as references for this article and both sources provide a sound overview as to the underlying technology and future evolution of IMS based IP Television.
Antonis Hontzeas - Antonis Hontzeas has been in the forefront of the Telecommunications industry for over twenty years. Tenures include positions ranging ...
