GISP: Global Information Sharing Protocol - A Distributed Index for Peer-to-Peer

This paper proposes GISP (Global Information Sharing Protocol), which aims at a world-wide distributed index. A distributed index consists of a set of pair data (key, value) shared by many peers. Each peer is responsible for a part of the index based on a hash function. Every peer is basically flat and there is no single point of failure. A distributed index is an essential building block for peer-to-peer systems. The design of GISP is simple, open, and easy to develop. GISP deals with peer heterogeneity and undesirable peers. Each peer promotes its strength so that stronger peers contribute more than weaker peers. Redundancy is important for defending against undesirable peers. Peers replicate pair data so that each pair data of the index is covered by several peers. There is a project at jxta.org for developing GISP. JXTA is a set of protocols for a peer-to-peer platform and provides a Java reference implementation. At the project, GISP is implemented in the Java language on JXTA. By building GISP on top of JXTA, a peer could reach a peer behind a firewall and even a peer in a different network transport. Jnushare is another project at jxta.org, which is to provide an application of GISP. Using Jnushare, people would share information such as files, messages and bookmarks.