Distributed authentication for peer-to-peer networks

Abstract

A public key infrastructure is generally (and effectively) used for cryptographically secure authentication in networks. Ad-hoc networks are formed in a haphazard manner. Security services for ad-hoc networks cannot assume the existence of a particular infrastructure. Peer-to-peer technology is promising in addressing security issues in ad-hoc networks. We provide a novel; cryptographically secure representation of trust based on secure groups - troupes. We show how troupes can be constructed in a distributed manner using RSA accumulators. Troupe-membership is verified using the zero-knowledge protocol of modular exponentiation. Each node in a group has an identity within a group, but it is not required to reveal the identity during verification. This trust model is not centrally controlled and can be deployed incrementally in the network. This paper presents protocols and a prototype implementation of the troup based authentication system.