A Push-Based VoIP Service for an Internet-Enabled Mobile Ad Hoc Network

VoIP (Voice over IP) services are gaining more popularity recently. This work considers providing VoIP services in an Internet-enabled mobile ad hoc network (MANET). Since MANET does not have a fixed connection to the Internet, we propose to attach one or multiple cellular interfaces to the gateway of the MANET to establish the connection so that users can enjoy mobile VoIP services. Connecting cellular interfaces, however, incurs charges and power consumption. Considering that voice calls do not always exist, it is desirable to allow the gateway to disconnect these cellular interfaces while idle. To guarantee that users inside the MANET will not lose any incoming call, we propose a push mechanism through short message services (SMS) to “wake up” these cellular interfaces. We show the detail signaling to achieve the push mechanism. The proposed system is fully compatible with existing SIP standards. In addition, the gateway allows multiple MANET users to share its cellular interfaces. Our prototyping experience and some experimental results are also reported. Index Terms — MANET (Mobile Ad-Hoc network), SIP (Session Initiation Protocol), VoIP (Voice over IP), push mechanism, wireless network