A hierarchical resource locating and routing for SIP-based telephony systems

SIP provides powerful capabilities for building audio conferencing services. However, the scalability for SIP-based telephony systems is mainly limited by both the capability of server and the availability of bandwidth. Based on the study of the SIP and P2P protocol, the paper proposes a pure hierarchical P2P architecture for SIP-based telephony systems. The architecture can dynamically increase the number of users without negative influence on the stability of system. Experimental results show that the hierarchical P2P architecture can significantly reduce both resource lookup latency and physical hops.