aganga's bittorrent [13 articles]

Abstract

The BitTorrent (BT) file sharing protocol is popular due to its scalability property and the incentive mechanism to reducefree-riding. However, in designing such P2P file sharing protocols, there is a fundamental "tussle" between keeping peers,specially the more resourceful ones, in the system for as long as possible to help the system achieve better performance andallowing peers finish their download as quickly as possible. The current BT protocol represents only "one" possible implementationin this whole design spectrum. In this paper, we characterize ...

Abstract

Recent research efforts have shown that the popular BitTorrent protocol does not strictly enforce fairness and allows free-riding, mainly via optimistic unchokes. This paper proposes a BitTorrent-like protocol, that encourages peers of similar upload bandwidth to be buddies— peers collaborating for mutual benefit. Buddy peers mostly satisfy their download needs through their buddies and perform optimistic unchokes only when absolutely necessary. As a result, the buddy protocol improves fairness via explicit cooperation between buddies, and limits bandwidth spent on random optimistic ...

Abstract

A fundamental problem with many peer-to-peer systems is the tendency for users to “free ride”—to consume resources without contributing to the system. The popular file distribution tool BitTorrent was explicitly designed to address this problem, using a tit-for-tat reciprocity strategy to provide positive incentives for nodes to contribute resources to the swarm. While BitTorrent has been extremely successful, we show that its incentive mechanism is not robust to strategic clients. Through performance modeling parameterized by real world traces, we demonstrate that ...

Abstract

In this paper, we conduct extensive simulations to understand the properties of the overlay generated by BitTorrent. We start by analyzing how the overlay properties impact the efficiency of BitTorrent. We focus on the average peer set size (i.e., average number of neighbors), the time for a peer to reach its maximum peer set size, and the diameter of the overlay. In particular, we show that the later a peer arrives in a torrent, the longer it takes to reach its ...

Abstract

Most current P2P file sharing systems treat their users as anonymous, unrelated entities, and completely disregard any social relationships between them. However, social phenomena such as friendship and the existence of communities of users with similar tastes may be well exploited in such systems, to increase their usability and performance. In this paper we present a novel social-based P2P file-sharing paradigm that exploits social phenomena by maintaining social networks and using these in... ...

Abstract

Peer-to-peer protocols play an increasingly instrumental role in Internet content distribution. It is therefore important to gain a complete understanding of how these protocols behave in practice and how their operating parameters affect overall system performance. This paper presents the first detailed experimental investigation of the peer selection strategy in the popular BitTorrent protocol. By observing more than 40 nodes in instrumented private torrents, we validate three protocol properties that, though believed to hold, have not been previously demonstrated experimentally: the ...