1. 1 Optimal Resource Placement in Structured Peer-to-Peer Networks Authors: W. Rao, L. Chen, A.W.-C. Fu, G. Wang Source: IEEE Transactions on Parallel and Distributed Systems, vol. 21, no. 7, pp. 1011-1026, 2010 Speaker: Huan-Chin Hsu ( 徐煥欽 ) Date: 2010/10/08

2. 2 Outline Introduction –Chord –Symphony –Problems Proposed scheme –Resource placement strategy –PCache –PRing Experimental results Conclusions Comments

3. 3 Chord

4. 4 Symphony

5. 5 Problems Skewed Popularity –Popular objects create excessive workload –Overloading problem Where to place the resources? How many resources are needed?

6. 6 Resource placement strategy

7. 7 Placement strategy in symphony

8. 8 PCache architecture

9. 9 PCache Load Balancing Popularity Estimation –Aggregation protocol Consistency Maintenance –Object version

10. 10 PRing in Symphony

11. 11 Experimental results(1/4) Solving MAX_PERF Problem with N = 4000 to Evaluate the Achieved Average Lookup Hops H

12. 12 Experimental results(2/4) Solving MIN_COST Problem with N = 4000 to Find the Consumed Replicas (×1000)

13. 13 Experimental results(3/4)

14. 14 Experimental results(4/4)

15. 15 Conclusions Propose a resource allocation solution PCache which can optimally trade off the performance gain and paid cost. And the optimal ring structure, PRing with better results than existing works.

16. 16 Comments Web object version problem in PCache. PRing still skewed popularity. PCache not suitable for use in large size files.