A P2P-IPTV Architecture Based On IP Multimedia Subsystem

The rapid development of network technologies leads to the thousand of requirements of network service needed by people. IPTV (Internet Protocol Television) is a system where a digital television service is delivered by using Internet Protocol over a network infrastructure. The advantage of IPTV is carrying out true inter-active, not only received broadcast information, and also interactive between user and service provider. As the core of Next Generation Network (NGN), IMS(IP Multimedia Subsystem) core network technology becomes the main platform carry IPTV service. IMS is a subsystem to support IP multimedia service proposed by 3GPP in Release 5, its key characters are using SIP protocol and independent of accessing. Many International Standard Organizations have done some research on the IPTV service based on IMS, in order to make IMS to be the universal platform support IPTV based on SIP session, and support fix and mobile access method simultaneously.The transmission of media resource is the most important technology. Now the three main transmission modes, include C/S (Client/Server) mode, multi-cast mode and CDN (Content Delivery Network) mode, all have their disadvantage and limit. Nowadays, Peer-to-Peer (P2P) technology has gained its popularity in Internet. It's predictable that P2P will be the best network technology resolving the media stream transmission issue. Bring P2P to IPTV service system will make system resource more utilized, traffic mode more reasonable, and reduce the pressure of center content server, at the same time, the calculate and storage resource of the computers in this system will be utilized.Although P2P technology has a lot of advantage in transmission stream media, it lacks of effective management and control mechanism, so how to make use of P2P with management capability in IPTV service architecture is the key research point in this paper. So we have proposed a novel P2P-IPTV architecture based on IMS, which integrates the efficient management of IMS and transmission method of P2P. We have proposed to add an IMS-P2P Layer, between Signaling Layer and Media Transmission Layer. On this layer, a new functionality has been defined, which is called Super Management Node (SMN). SMN, as a super node, and the functionalities of Transmission Layer construct an administrable and half-distributed P2P Network to support IPTV service. For the reason that the huge successful in media stream transmission of P2P and the strong management of IMS, we believed that this new architecture will be able to support IPTV service more and more effective. In the future, more careful and in-depth research is worth doing on this architecture, and will be contributed for the development of next generation network.