Adaptation of SIP protocol to Ad hoc Networks

Abstract

Through This thesis we propose a new approach to fix the problem related to the deployment of SIP protocol in Ad Hoc Networks. In fact in an Ad hoc network context, there is no available centralized architecture to accommodate different key servers for SIP operations.

The main idea of this new approach, which we have named VNSIP (Virtual Network for Session Initiation Protocol), is to self-organize the ad hoc network using a virtual backbone, and then this virtual network will be used as architecture to ensure different roles of SIP entities. We have evaluated performances of our technique using comparison with TCA approach, which is considered as one of the most satisfying solution to adapt SIP to Ad hoc networks.

During this thesis we have treated the notion of QoS in MANET (Mobile Ad hoc Networks) as well. In fact we will explain, at the end of the comparison, that despite the fact that our solution offers overall better results than TCA, it nevertheless suffers from a high consumption of bandwidth, which forced us to enhance VNSIP performance regarding this constraint of bandwidth. Therefore we have designed a new algorithm to enhance QoS inside MANETs. We have named this algorithm MCAC (MANET Call Admission Control). This algorithm counts the number of simultaneous calls or sessions inside the MANET, and refuses the establishment of new sessions when a maximum number of simultaneous calls is reached. By this manner we can control the bandwidth of the MANET and consequently guarantee a good QoS.

To highlight VNSIP approach, it was necessary to define a scope of works of this thesis. Indeed, we will present UCIAN (University Communication at Intelligent Ad hoc Network) project. It’s a VNSIP-based application, dedicated to university teacher. It will allow users to benefit from SIP services, especially IM (Instant Messaging) and Presence services without using any pre-existed architecture.