Drive Us-P2P-SIPPeer.ppt

March 12, 2001 Internet routing reliability P2P-SIPPeer to peer Internet telephony using SIP Kundan Singh and Henning Schulzrinne Columbia University, New York June 2005 /IRT/p2p-sip Overview Introduction What is P2P? and SIP? Why P2P-SIP? Architecture SIP using P2P vs P2P over SIP; Components that can be P2P Implementation Choice of P2P (DHT); Node join, leave; message routing Conclusions and future work What is P2P? Share the resources of individual peers CPU, disk, bandwidth, information, … P2P goals Resource aggregation - CPU, disk, … Cost sharing/reduction Improved scalability/reliability Interoperability - heterogeneous peers Increased autonomy at the network edge Anonymity/privacy Dynamic (join, leave), self organizing Ad hoc communication and collaboration Definition fuzzy both client and server? true for proxy no need for central server true for SIP-based media SIP can be e2e proxy functions distributed among end systems Distributed Hash Table (DHT) Types of search Central index (Napster) Distributed index with flooding (Gnutella) Distributed index with hashing (Chord) Basic operations find(key), insert(key, value), delete(key), but no search(*) Why P2P-SIP? How to combine SIP + P2P? SIP-using-P2P Replace SIP location service by a P2P protocol P2P-over-SIP Additionally, implement P2P using SIP messaging SIP-using-P2P Reuse optimized and well-defined external P2P network Define P2P location service interface to be used in SIP Extends to other signaling protocols P2P-over-SIP P2P algorithm over SIP without change in semantics No dependence on external P2P network Reuse and interoperate with existing components, e.g., voicemail Built-in NAT/media relays Message overhead What else can be P2P? Rendezvous/signaling Configuration storage Media storage Identity assertion (?) Gateway (?) NAT/media relay (find best one) Our P2P-SIP approach Unlike server-based SIP architecture Unlike proprietary Skype architecture Robust and efficient lookup using DHT Inter