Efficient and Secure Identity-Based Onion Routing

Onion routing protocols achieve low-latency anonymous communication on public networks. Up to date, many onion routing protocols have been proposed, such as Tor network, in order to implement the anonymous network connection in the public networks. Although the previous schemes’ multi-pass cryptographic circuit construction appears satisfactory, their circuit construction protocols have some drawbacks with regard to the efficiency and security. This paper presents a novel identity-based onion routing protocol that allows users to establish anonymous channels over a public network. The proposed scheme eliminates iterative and interactive symmetric key agreement procedures between users and onion routers by embedding a circuit construction into the non-interactive message delivery process. It significantly improves the storage and communication costs required from each user and onion router compared to the previous onion routing protocols, while requiring comparable computation cost to them.