Understanding Peer Exchange in BitTorrent Systems

Author

Wu, Di ; Dhungel, Prithula ; Hei, Xiaojun ; Zhang, Chao ; Ross, Keith W.

Author_Institution

Sun Yat-Sen Univ., Guangzhou, China

fYear

2010

fDate

25-27 Aug. 2010

Firstpage

1

Lastpage

8

Abstract

Peer Exchange (PEX), in which peers directly exchange with each other lists of active peers in the torrent, has been widely implemented in modern BitTorrent clients for decentralized peer discovery. However, there is little knowledge about the behavior of PEX in operational systems. In this paper, we perform both passive measurements and Planetlab experiments to study the impact and properties of BitTorrent PEX. We first study the impact of PEX on the download efficiency of BitTorrent. We observe that PEX can significantly reduce the download time for some torrents. We then analyze the freshness, redundancy and spread speed of PEX messages. Finally, we also conduct large- scale Planetlab experiments to understand the impact of PEX on the overlay properties of BitTorrent.

Keywords

peer-to-peer computing; BitTorrent systems; PEX; Planetlab experiments; passive measurements; peer discovery; peer exchange understanding; Book reviews; Crawlers; Extraterrestrial measurements; IEEE Communications Society; Peer to peer computing; Protocols; Redundancy;

fLanguage

English

Publisher

ieee

Conference_Titel

Peer-to-Peer Computing (P2P), 2010 IEEE Tenth International Conference on

Conference_Location

Delft

Print_ISBN

978-1-4244-7140-9

Electronic_ISBN

978-1-4244-7139-3

Type

conf

DOI

10.1109/P2P.2010.5569967

Filename

5569967