Research On Key Management Scheme In VoIP System

With the expansion of network bandwidth and the acceleration of the network convergence process, VoIP technology has been widely used. It becomes a multimedia communication technology which contains audio, image, video and data and supports various intelligent services in two-party or multi-party communication systems. Due to the openness of IP network and the security vulnerabilities of related communication protocols, the attack against to signaling protocols and media stream becomes much easier in VoIP communication systems, and the security problem is very prominent.This paper originates from national project of the 11th Five-year Plan, and mainly studies the key management scheme in VoIP system. Firstly, the related communication protocols in VoIP communication systems, major security threats and the main security strategies are analyzed and studied. The paper also discusses the importance of the key safety and key management in security communication systems. Secondly, a kind of two-party authentication key agreement scheme based on identity and bilinear Diffie-Hellman hypothesis is designed. Meanwhile, a kind of distributed multi-party key management scheme based on ternary tree and bilinear Diffie-Hellman hypothesis is presented. Analysis shows that both schemes can ensure the security of VoIP communication systems. Finally, an embedded VoIP security terminal applying two-party authentication key agreement scheme is designed and achieved, which guarantees the communication security in VoIP system.