YAPPERS: a peer-to-peer lookup service over arbitrary topology

Abstract

Existing peer-to-peer search networks generally fall into two categories: Gnutella-style systems that use arbitrary topology and rely on controlled flooding for search, and systems that explicitly build an underlying topology to efficiently support a distributed hash table (DHT). In this paper, we propose a hybrid scheme for building a peer-to-peer lookup service over arbitrary network topology. Specifically, for each node in the search network, we build a small DHT consisting of nearby nodes and then provide an intelligent search mechanism that can traverse all the small DHTs. Our hybrid approach can reduce the nodes contacted for a lookup by an order of magnitude compared to Gnutella, allows rapid searching of nearby nodes through quick fan-out, does not reorganize the underlying overlay, and isolates the effect of topology changes to small areas for better scalability and stability.