Optimizing SIP Service Provisioning in Internet Connected MANETs

Recently, mobile ad-hoc networks (MANETs) have gained a lot of attraction because they are flexible, self-configurable and fast to deploy. Systems beyond 4G are likely to consist of a combination of heterogeneous wireless technologies and naturally might comprise MANETs as one component. In order to provide multimedia services such as voice over IP in such environment, support for session initiation protocol (SIP) is essential. A MANET is a decentralized collection of autonomous nodes but a SIP infrastructure requires centralized proxies and registrar servers. In this paper, we first study the implications of using standard SIP architecture in Internet connected MANETs. We analyze limitations of SIP service scalability when centralized proxies/registrars located in the access network are used by MANET nodes. Finally, we present alternative approaches to provide SIP services in such environment to avoid current limitations