Efficient Certificate Based One-pass Authentication Protocol for IMS

Abstract

IP Multimedia Subsystem (IMS) ensures quality voice and video transmission to users in next generation network. In IMS each user entering from another network like UMTS or Voice over LTE (VOLTE) or 5G has to authenticate itself. Due to unnecessary authentication, high signaling can result in congestion. This paper presents a Certificate based One-pass Authentication Protocol (COAP) that avoids duplicate authentication steps and achieve efficient authentication through the use of digital certificates. It restricts the repetition of full authentication until the certificate expires. We have also eliminated four messages during authentication by utilizing the existing credentials of UE shared earlier. Moreover, we have utilized backup servers during peak hours to reduce congestion, call termination and support more users. A testbed is setup to perform different experiments to validate performance of proposed and existing schemes. COAP achieves better bandwidth consumption, transmission cost, response time and signaling traffic load to reduce the congestion problem.