A Churn-Resistant Strategy for a Highly Reliable P2P System

Abstract

This paper proposes a churn-resistant strategy designed on top of a highly reliable P2P overlay network [1], with degree 1 2∆ + 2, where ∆ is the degree of a De Bruijn digraph [2]. We show that when each node in the network periodically retransmits only one KEEPALIVE message to one of its neighbors in the network, any node's failure can be detected within an optimal timeout. As a major contribution, we demonstrate that even in failure situations the lookup of any available resource is achieved with the lowest possible maintenance overhead O(1) along the shortest path of length DCMR = log ∆ (N (∆ − 1) + ∆) − 1 with N being the maximal number of nodes in the network. 1 The degree of a vertex ∆(x) is the number of vertices adjacent to x. The degree of a graph G is ∆G = max {∆(x), x ∈ V }. With G defined as G = (V, E), where V is the set of vertex and E is the set of Edge of G.