Analysis of Peer to Peer Communication in Networks 2/15/10 - PowerPoint PPT Presentation

Analysis of Peer to Peer Communication in Networks 2/15/10 Prestige Lecture Purdue University 1

Outline of presentation  Overview  Fluid analysis (after Massoulie and Vojnovic)  Direct stochastic analysis (work with Ji Zhu)  Discussion 2/15/10 Prestige Lecture Purdue University 2

Traditional File Service 2/15/10 Prestige Lecture Purdue University 3

Peer-to-peer File Service Service capacity scales with demand ! Scalable Robust 2/15/10 Prestige Lecture Purdue University 4

1 st Generation P2P Systems Entire file uploaded in one shot Users wait till entire file is received before relaying BUT if file size is large, 1. Long delay before users become useful. 2. If users depart mid-way, a lot of upload time wasted. e.g. Gnutella, KaZaa 2/15/10 Prestige Lecture Purdue University 5

2 nd Generation P2P Systems File split into pieces Peers can start serving pieces without waiting for entire file. More effective at serving large files. e.g. BitTorrent, eDonkey 2/15/10 Prestige Lecture Purdue University 6

Relative Popularity 2/15/10 Prestige Lecture Purdue University 7

File Types in eDonkey 2/15/10 Prestige Lecture Purdue University 8

Flash Crowds Flash Crowd: large number of users start requesting same file simultaneously Scenario where P2P system design tested most severely. Users requesting LoTR III on BitTorrent 2/15/10 Prestige Lecture Purdue University 9

Our Motivation To understand second-generation peer-to-peer systems Peer selection strategies Piece selection strategies Push vs. pull Effects of heterogeneous link speeds Effects of network topologies ISP friendly operation Applications: file transfer, live streaming, video on demand, online interactive gaming or instruction, . . . 2/15/10 Prestige Lecture Purdue University 10

peers collecting peers pieces (coupons) pieces initial seeding seed 2/15/10 Prestige Lecture Purdue University 11

peers collecting peers pieces (coupons) pieces initial seeding seed 2/15/10 Prestige Lecture Purdue University 12

peers collecting peers pieces (coupons) pieces initial seeding seed 2/15/10 Prestige Lecture Purdue University 13

peers collecting peers pieces (coupons) pieces initial seeding seed 2/15/10 Prestige Lecture Purdue University 14

peers collecting peers pieces (coupons) pieces initial seeding 2/15/10 Prestige Lecture Purdue University 15

peers collecting peers pieces (coupons) pieces initial seeding seed 2/15/10 Prestige Lecture Purdue University 16

peers collecting pieces (coupons) seed 2/15/10 Prestige Lecture Purdue University 17

peers collecting pieces (coupons) seed 2/15/10 Prestige Lecture Purdue University 18

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peers collecting pieces (coupons) seed 2/15/10 Prestige Lecture Purdue University 20

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peers one club pieces (members have all pieces except piece one) normal young seed peers infected young peers 2/15/10 Prestige Lecture Purdue University 22

one club normal seed young peers infected young peers 2/15/10 Prestige Lecture Purdue University 23

one club normal seed young peers infected young peers 2/15/10 Prestige Lecture Purdue University 24

one club normal seed young peers infected young peers 2/15/10 Prestige Lecture Purdue University 25

0 i 1 2 K-1 0 i j 1 2 K-1 2/15/10 Prestige Lecture Purdue University 26

0 i 1 2 K-1 0 i j 1 2 K-1 2/15/10 Prestige Lecture Purdue University 27

Discussion 2/15/10 Prestige Lecture Purdue University 28

Discussion (continued) one club normal young peer (members have all pieces except piece one) infected young peer 2/15/10 Prestige Lecture Purdue University 29

Discussion (continued) 2/15/10 Prestige Lecture Purdue University 30

Discussion (continued) 2/15/10 Prestige Lecture Purdue University 31

Thanks! 2/15/10 Prestige Lecture Purdue University 32