SIP-based VoIP-over-MPLS Architecture Design and System Development for Interactive and Secure Multimedia Services

Abstract

With the success of Internet and the advances of network technologies, the number of multimedia users increases dramatically in recent years. The next generation communication networks shall provide interactive and secure multimedia services to the public. Among multimedia services, VoIP is one of the most popular applications due to its low cost compared to conventional voice services via the Public Switched Telephone Network (PSTN). However, inherited from its interactive and real-time nature, it is very sensitive to network congestions and it requires more stringent quality of service (QoS). To carry good quality of voice over an IP network, it needs both a good signaling protocol as well as high speed backbone to forward IP packets efficiently. The emerge of the Session Initiation Protocol (SIP) and the Multi-Protocol Label Switching technology (MPLS) provide a good QoS solution to the VoIP applications. The former provides an easy and flexible signaling strategy for the IP environment, while the later provides QoS guarantees with the use of the traffic engineering. In this paper, we propose a novel architecture to integrate these two technologies, which is suitable for VoIP applications with secure and QoS guarantees. This VoIP-over-MPLS architecture employs the SIP protocol for signaling to set up call connection and uses the MPLS core network to forward packets efficiently. Especially, we put emphasis on the necessary components to provide interactive and secure services. This architecture comprises three major parts: Edge devices, access network, and the MPLS core network. The necessary elements and requirements are described in this paper, which is followed by the modified SIP registration and signaling process to provide the secure and traffic engineering functionalities.