Abstract
The unstable nature of MANETs over different types of wireless topologies and mobility models affects the Quality of Service (QoS) for real time applications such as Voice over IP (VoIP). One of the most efficient signaling systems for VoIP applications is the Session Initiation Protocol (SIP) which is mainly used to initiate, manage, and terminate VoIP calls over different types of IP based network systems. As a part of upgrading to Next Generation Network, MANETs will be considering IPv6 for different types of applications and devices. Therefore, SIP signaling over IPv6 MANETs needs to be investigated with different QoS performance metrics such as bandwidth, packet loss, delay and jitter. In this paper, an evaluation of SIP signaling is conducted for SIP based VoIP calls using GSM voice codec system over MANETs with Static, Uniform, and Random mobility models. This evaluation considered AODV as a reactive routing protocol and OLSR as a proactive routing protocol over both IPv4 as well as IPv6. The evaluation study of SIP signaling examined call setup time, number of active calls, number of rejected calls and calls duration. The results of this study show that, in general, IPv4 has better performance over different types of mobility models, while IPv6 upholds longer delays and poor performance over Random mobility models.