Safe Peer-to-Peer Self-downloading

摘要

Peer-to-peer applications share files between users them selves rather than downloading files from file servers. Self-downloading protocols have the property that eventually, every user downloads only from other users. This paper considers efficient ways of dividing files into segments so that users can exit the system as soon as file downloading is complete. One vulnerability of file sharing between peers is the possibility that files or segments could be counterfeit or corrupt. Protocols that are d-safe tolerate some number of instances of faulty segments in a file being downloaded, because each segment is downloaded d times before being uploadable. It is shown that d-safe self-downloading is possible for a sufficiently large arrival rate of users to the system. In addition, the paper presents upper and lower connectivity and sharing bounds for d = 2.