Supporting mobility in an IMS-based P2P IPTV service: A proactive context transfer mechanism

In recent years, IPTV has received an increasing amount of interest from the industry, commercial providers and the research community, alike. In this context, standardization bodies, such as ETSI and ITU-T, are specifying the architecture of IPTV systems based on IP multicast. An interesting alternative to support the IPTV service delivery relies on the Peer-to-Peer (P2P) paradigm to distribute and push the streaming effort towards the network edge. However, while P2P IPTV was studied in fixed access technologies, there has been little attention paid to the implications arising in mobile environments. One of these involves the service handover when the user moves to a different network. By analyzing previous work from the perspective of an IPTV service, we concluded that a proactive approach is necessary for the handling of inter-network handovers. In this paper, we propose a new general handover mechanism for the IP Multimedia Subsystem (IMS), while studying its applicability to a P2P IPTV service. Our solution, called proactive context transfer service, incorporates the existing IEEE 802.21 technology in order to minimize the handover delay. The proposal is validated by comparing it against solutions derived from previous work. 2010 Elsevier B.V. All rights reserved.