JustTorrent: Value Based - Fairer and Faster Protocols for P2P File Sharing

Year 2017, Volume: 1 Issue: 1, 1 - 10, 31.03.2017

Ozan Okumuşoğlu Muhammed Furkan Bayraktar Alptekin Küpçü

Abstract

BitTorrent
is a highly effective peer-to-peer file sharing protocol. It allows clients to
share large files over the network by dividing a file into pieces and dividing
pieces into blocks. Studies so far showed that BitTorrent’s tit-for-tat
strategy does not provide fairness. Thus, there were some proposed
modifications and extensions. Unfortunately, the previous attempts at providing
fairness fail when pieces are not of equal value. In this paper, we consider
value-based fairness in BitTorrent, for the first time, as we show that
different pieces in a single torrent may be of different value. We suggest two
separate modifications to increase fairness and decrease average download time
in the BitTorrent protocol. The results of our modifications show us that via
fair mechanisms, one may provide security against adversaries who only request
valuable pieces in the system. Moreover, one may achieve around 30% better
average download times for peers in the system, while remaining fair.

Keywords

BitTorrent, fairness, fair exchange, peer-to-peer

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