An Internet SIP Gateway for Ad-hoc Networks

Various forms of ad-hoc networking are slowly emerging. However, a wider diffusion of ad-hoc networking in everyday life will only be possible if existing common applications are adapted for use in ad-hoc networks. There has been some work on adapting Internet-based applications to function in ad-hoc networks. Yet, in order to make ad-hoc networking even more useful and interesting to people, applications must also be able to connect to the Internet. Many new Internet applications are based on sessions, e.g., instant messaging, VoIP and multimedia communications. The session initiation protocol (SIP) is a popular protocol to manage sessions in IP networks, based on centralized servers, and application-level routing. However, in order to establish SIP sessions between an ad-hoc network and the Internet, some logic must be built in the ad-hoc gateway node to make messages flow correctly to and from the ad-hoc network. In this paper, we present an intelligent SIP gateway that makes it possible to route messages properly between ad-hoc networks, and the Internet, even when the ad-hoc IP addresses are not globally routable