An investigation into expanding the capabilities of peer-to-peer networks:combining centralized network infrastructure into decentralized peer-to-peer network topology

Abstract

The Session Initiation Protocol (SIP) has been adopted by the 3rd Generation Partnership Project (3GPP [30]) as the standard signalling for session management over wireless networks. It’s the basis of a wide range of IP multimedia services. SIP relies on centralized servers according to its standard specifications and current usage. However, server based approaches are typically non-scalable as they may involve a large amount of capital investment and costly maintenance, also administrative efforts would be required to maintain the network infrastructure. This would be suitable for large commercial firm but not practical for small organizations, especially in the home environment. Therefore research has started on the integration of Peer-to-Peer (P2P) principles to SIP to take advantage of decentralization in last decade. Peer-to-Peer network is based on decentralized and distributed network architecture; In contrast to the centralized client-server network, each individual connected node (or called peer) on peer-to-peer network, is both resource consumer and supplier in same time. In peer-to-peer networks, tasks like resource publishing, sharing and discovering are shared amongst multiple interconnected peers, who voluntarily make their own resources available to other connected network participants. The Peer-to-Peer network has the ability of self-organizing and great expandability; therefore peer-to-peer network is great platform for small organization and home environment. This thesis investigates the possibility of integrating SIP into a JXTA-based P2P infrastructure, with the aim to contribute to research in decentralizing the SIP protocol. This proposed theory is to directly integrate SIP into P2P overlay with self-organized proxies and distributed registrars. Unlike other proposed approaches of P2P-SIP architectures to date, this proposed theory does not extend SIP message header and is middleware independent. Also the selforganizing mechanisms are initiated amongst each participant voluntarily, not passively. Therefore the proposed theory in this report would theoretically be able to interoperate with legacy SIP and/or JXTA platforms to ensure the compatibility and intercommunication ability, and most importantly is to maintain SIP registrar within the network constantly, also actively self-organizing to optimize the network topology from time to time