A performance study for IPv4–IPv6 translation in IP multimedia core network subsystem

Abstract

AbstractA Next Generation Network (NGN) is an advanced, packet‐based network that exploits broadband and QoS‐enabled transport technologies for enabling multimedia services. In NGNs, the principles and requirements of IP Multimedia Sub‐system (IMS), which are used to deliver the desired benefits, should be carefully examined and studied. Internet Protocol version 6 (IPv6) is adopted by Third‐generation Partnership Project (3GPP) to solve address storage problem and provide new features (e.g. plug‐and‐play and mobility) for IMS. However, in the early stage of IPv6 deployment, the existing Voice‐over‐IP (VoIP) networks support Internet Protocol version 4 (IPv4) only. For IPv4–IPv6 interworking between IMS and the existing VoIP networks, the IMS‐Application Level Gateway (IMS‐ALG) and the Transition Gateway (TrGW) are proposed to translate Session Initiation Protocol (SIP) and Real‐time Transport Protocol (RTP) packets, respectively. In this paper, we focus on the IPv4–IPv6 translation for RTP packets, which is the bottleneck of VoIP performance. Specifically, we developed a TrGW called National Information and Communications Initiative (NICI)‐TrGW. In NICI‐TrGW, we perform IPv4–IPv6 translation at the Linux kernel and adjust the header room of kernel‐level packet buffer for each packet to reduce memory‐copy operations. We evaluate the performance of NICI‐TrGW and the existing solutions by using the SmartBits. Our study indicates that NICI‐TrGW outperforms the existing solutions in terms of three different output measures including packet loss rate, maximum throughput, and average latency. Copyright © 2009 John Wiley & Sons, Ltd.