Modeling Unavailability in Peer-to-Peer Systems

Abstract

In this paper we model peer-to-peer systems where content may become unavailable. First, using Markov Chains we capture the impact of parameters such as the server upload rate and the popularity of the files on the performance of the system. Then, we show the applicability of our model to the problem of optimal bundling. Bundling files together, rather than disseminating them separately, is a possible solution to improve availability in BitTorrent.