1. STATE KEY LABORATORY OF NETWORKING & SWITCHING BEIJING UNIVERSITY OF POSTS AND TELECOMMUNICATAIONS 2007-1-5 A Semantic Peer-to- Peer Overlay for Web Services Discovery Shuang Kai

2. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-52 Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

3. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-53 Introduction-1 service discovery mechanisms –centralized registry UDDI or DAML-S matchmaker –decentralized approach centralized registry –single point failure –performance bottleneck

4. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-54 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

5. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-55 Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

6. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-56 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

7. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-57 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

8. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-58 Characteristic Vector - 2 service description: Advertisement1 = {C 7, C 6, C 5, C 4 } CV={10, 11, 0000, 0100}.

9. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-59 Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

10. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-510 Semantic overlay node architecture -1

11. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-511 Semantic overlay node architecture -2

12. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-512 Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

13. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-513 Routing Table multiple rows each rows holds a number of entries semantic matching of the prefix up to an element in the CV

14. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-514 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

15. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-515 Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

16. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-516 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

17. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-517 Message Routing and Locating

18. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-518 Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

19. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-519 Example Message ID C 3 C 7 C A C 0 Exact Subsume

20. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-520 Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

21. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-521 Experimental Evaluation - 1

22. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-522 Experimental Evaluation - 2

23. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-523 Agenda Introduction Thoughtway of our method Semantic overlay node architecture Routing Table & Neighborhood Table Message Semantic Matching & Routing Example Experimental Evaluation Conclusion

24. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-524 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

25. STATE KEY LABORATORY OF SWITCHING TECHNOLOGY AND COMMUNICATION NETWORK 2007-1-525 Thank you ！