The Case for a Hybrid P2P Search Infrastructure

Popular P2P le-sharing systems like Gnutella and Kazaa use unstructured network designs. These networks typ- ically adopt ooding-based search techniques to locate les. While ooding-based techniques are effective for locating highly replicated items, they are poorly suited for locating rare items. As an alternative, a wide vari- ety of structured P2P networks such as distributed hash tables (DHTs) have been recently proposed. Structured networks can efciently locate rare items, but they incur signicantly higher overheads than unstructured P2P net- works for popular les. Through extensive measurements of the Gnutella network from multiple vantage points, we argue for a hybrid search solution, where structured search techniques are used to index and locate rare items, and ooding techniques are used for locating highly repli- cated content. To illustrate, we present experimental re- sults of a prototype implementation that runs at multiple sites on PlanetLab and participates live on the Gnutella