A peer-to-peer overlay for the IP multimedia subsystem

The growth of the Internet and its popular services are forcing telecom operators to provide advanced services to their subscribers, as traditional voice services are no longer enough to attract more customers. To enable more innovative and value-added IP services and take advantage of the services that the Internet provides, the IP Multimedia Subsystem (IMS) is introduced. The IMS provides a complete access-agnostic architecture and framework that facilitates the convergence of the mobile network, removing the gap between the two most successful communication networks: cellular and Internet network. The harmonized All-IP platform has the potential to provide all Internet services with a more cost-effective and more efficient architecture than the circuit-switched networks do. However, by merging two of the most successful networks, the integration of two network models with different concerns and motivations is not without its problems, among which, the scalability issue is the most essential when supporting content delivery services. The purpose of this chapter is to study and design a new content delivery network infrastructure, PeerMob, merging the Peer-to-Peer technology with the IMS framework, which benefits IMS with scalability, reliability, and efficiency features coming with decentralized P2P architecture. The chapter also puts this P2P IMS paradigm under realistic network conditions and strenuous simulation to evaluate the performance of the P2P IMS system.