Decentralized supplementary services for Voice-over-IP telephony

As current Voice-over-IP (VoIP) systems encourage a direct communication between the callees they are similar in design to peer-to-peer (P2P) approaches. Therefore, we introduce a framework to build distributed supplementary services for VoIP. Some of these services like completion of calls on no reply or holding are already commonly established in public switched telephone networks or realized in centralized VoIP servers like Asterisk [1]. In order to foster the completely decentralization of these features we suggest corresponding services implemented on top of a structured P2P network. Using a resource-based approach new features can easily be deployed and announced.