1. 2006-05-191 Canon in G Major: Designing DHTs with Hierarchical Structure Prasanna Ganesan, Krishna Gummadi, Hector Garcia-Molina ICDCS2004 報告者 : 陳奕鈞

2. 2006-05-192 Outline Motivation Canon Crescendo Routing Crescendo Evaluation Conclusion

3. 2006-05-193 Motivation P-2-P Application –File sharing –Multi-media sharing –Collaborative computation –General purpose lookup directories

4. 2006-05-194 Canon Where is the paper “Canon in G Major”?

5. 2006-05-195 Hierarchy Design Single Point Over Head Isolating faults Adapting growth

6. 2006-05-196 Flat Design(DHT) No single point of failure

7. 2006-05-197 Flat & Hierarchical Design Flat Design –No single point of failure –P2P(DHT) Hierarchical Design –Isolating faults –Adapting growth –DNS

8. 2006-05-198 Canon System

9. 2006-05-199 Crescendo Chord Merged Chord

10. 2006-05-1910 Chord Circular N-bit ID space Node x links to succ( )

11. 2006-05-1911 Crescendo Merge –Merging multiple rings –Multi-level hierarchies Incremental –New node joins bottom up Links per node –log(n)

12. 2006-05-1912 Merging Merging Rule –Each node m in one ring creates a link to a node n in the other ring iff. a.n is the closest node that is at least distance away for some b.n is closer to m than any node in m’s ring

13. 2006-05-1913 Merging

14. 2006-05-1914 Routing Crescendo (intra-domain) Greedy Clockwise routing Path Locality -Fault isolation --Efficiency 0 -> 12

15. 2006-05-1915 Routing Crescendo (inter-domain) Path convergence :closest node to destination in the domain :same destination node same last node in the domain 0 -> 13 -Distributed Caching -Bandwidth savings 5 -> 13

16. 2006-05-1916 Other DHTs Chord => Crescendo CAN => Can-Can Symphony => Cacophony Kademlia => Kandy

17. 2006-05-1917 Evaluation Links/node Hops/query latency

18. 2006-05-1918 Number of Links vs. Number of Levels

19. 2006-05-1919 Levels vs. Routing Hops

20. 2006-05-1920 Path Locality

21. 2006-05-1921 Conclusion –Novel Idea –Poor motivation