LDEPTH: A low diameter hierarchical P2P network architecture

Abstract

In this paper, we present a new approach to designing a scalable, hierarchical overlay P2P system which provides highly efficient data lookup operations as well fault tolerance. Instead of using a distributed hash table (DHT) based approach, we propose the use of Linear Diophantine Equation (LDE) as the mathematical basis to realize a hierarchical P2P architecture. LDE provides a significantly lighter weight mechanism to create and maintain the overlaid P2P structure as compared to DHT based schemes. To the best of our knowledge, ours is the first work that proposes the use of LDEs in designing P2P topologies. In our proposed hierarchical P2P architecture, the number of hops required to search for a resource is independent of the number of nodes/peers in the network n and is instead bounded by (1 + r/2), r being the number of distinct resource types. For most practical purposes, r is significantly smaller than n and hence our proposed architecture provides a highly efficient resource look-up procedure. We have also presented algorithms for handling of new resources and peers joining and leaving the P2P network and fault tolerance in the event of peers crashing or leaving.