Abstract

Structured overlay networks are highly susceptible to attacks aimed at subverting their structure or functionalities. Although many secure architectural design proposals have been presented in the past, a widely accepted and comprehensive solution is lacking. Likir (Layered Identity-based Kademlia-like Infrastructure) is our solution for implementing a secure Peer-to-Peer network based on a Distributed Hash Table. Our purpose is to focus on three main goals: (1) providing security services and a secure overlay infrastructure against the vast majority of security threats on P2P systems, (2) dynamically creating a bridge between randomly generated peer identifiers and user identities, and (3) supplying the developer with a middleware API that can easily deal with peers' identities. Placing the emphasis on user identity results in a highly secure distributed framework which is very fitting for privacy-aware and efficient implementation of identity-based applications like social networking applications. Detailed security analysis and performance evaluation are provided. Moreover, an implementation of Likir is introduced and a case study is presented in order to show its practical use in a real-life example.