Empirical performance evaluation of peer-to-peer VoIP telephony using SIP

Peer-to-peer mechanisms are considered as one of the key innovative and user-friendly solutions for real-time Internet communication services. Eliminating server-based architecture, reducing or eliminating configuration effort, and allowing end-user devices to bring resources into the network, will reshape the network as we currently know it. This presents substantial opportunities for networks and services; however it is imperative to standardize concepts and functionalities in order to achieve successful integration and the much required interoperability. IETF working group P2PSIP is currently working on these specifications. The objective of this article is to analyze characteristics, procedures and mechanisms proposed with the P2PSIP concept and to conduct a performance analysis based on a prototype implementation of P2PSIP communication system in comparison with the centralized SIP approach. Our results confirm the P2PSIP approach as a feasible solution in the proposed SOHO environment, since the cost in terms of increased delay is moderate and below the recommended values for traditional and Internet telephony defined by the standardization organizations ITU-T and ETSI.