Quantitative analysis of 2-tier P2P-SIP architecture with ID-based signature

Abstract

SIP(Session Initiation Protocol) is IETF standard signaling protocol for VoIP (Voice over IP) and other multimedia services. Recently, there have been some efforts to propose P2P-SIP architecture, which makes use of a peer-to-peer network instead of registrar and location SIP servers in order to facilitate SIP user registration and location. However, existing P2P-SIP systems still have some problems. Current P2P-SIP lookup does not meet the requirement for low time delay in multimedia services. Furthermore, security procedure based on PKI for SIP message authentication requires verification of central authorities (CA) during message routing and certificates maintenance of intermediate nodes. It puts more delay in signaling as users increase in the P2P-SIP network. Therefore, we propose 2-tier P2P-SIP architecture, using ID-based signature which has more light-weight authentication procedure and decreases the session setup latency to some extent, and perform quantitative analysis of this architecture. ID-based signature allows users to verify digital signatures using only public information such as the user``s identity, so that it reduces the complexity and costs for establishing and managing public key of nodes. Based on the performance analysis and simulation results, our proposed 2-tier P2P-SIP architecture achieves better scalability as well as shorter session setup latency than PKI-based P2P-SIP architecture.