STATE KEY LABORATORY OF NETWORKING & SWITCHING BEIJING UNIVERSITY OF POSTS AND TELECOMMUNICATAIONS A Semantic Peer-to- Peer Overlay for Web Services Discovery Shuang Kai

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Introduction-1 service discovery mechanisms –centralized registry UDDI or DAML-S matchmaker –decentralized approach centralized registry –single point failure –performance bottleneck

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Introduction-2 based on P2P technology –unstructured P2P network limitation on the scalability –structured P2P networks based on DHT logn routing hops – network of size n nodes exact match

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Thoughtway of our method structured P2P semantic method different matching degree extends the Plaxton mesh –dynamic semantic overlay network –keyword prefix routing to semantic prefix routing

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Characteristic Vector - 1 semantic service description –OWL-S or WSMO characteristic vector –a series of numeric string –extract service’s information input, output, Pre-conditions and Effects ontological concept

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Characteristic Vector - 2 service description: Advertisement1 = {C 7, C 6, C 5, C 4 } CV={10, 11, 0000, 0100}.

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Semantic overlay node architecture -1

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Semantic overlay node architecture -2

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Routing Table multiple rows each rows holds a number of entries semantic matching of the prefix up to an element in the CV

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Neighborhood Table Contains the nodeID and IP address of the peers Set of peers that are closest to the local peer –Based on semantic similarity

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Semantic Matching Degree Exact –If advertisement S and request Q are equivalent –S ≡ Q PlugIn –If S could always be used for Q –S is a plug-in match for Q, Q ⊆ S. Subsume –If S is more general than Q –S is a Subsume match for Q, S ⊆ Q

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Message Routing and Locating

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Example Message ID C 3 C 7 C A C 0 Exact Subsume

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Experimental Evaluation - 1

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Experimental Evaluation - 2

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Conclusion Our System –support semantic matching ontological concept encoding scheme –based on the structured overlay network dynamic Plaxton mesh-like network Future work –improve the usability of this system

STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK Thank you ！