Self-adaptive routing protocols for integrating cellular networks, WLANs, and MANETs

A growing need to have ubiquitous connectivity has motivated our research to provide continuous connection between various wireless platforms such as cellular networks, WLANs and MANETs. In this paper we consider integration at the routing layer and propose two adaptable routing protocols (IRP-RD and IRP-PD) that exploit topology information stored at the fixed network components (cellular Base Stations and WLAN Access Points) for the route discovery and maintenance processes. Our proposed protocols can provide connectivity to the cellular network and/or WLAN hotspots through multi-hop routing, while differ in the gateway discovery approach used. In IRP-RD, multi-hop routes to gateways to the cellular network or WLAN hot spots are discovered on demand, while in IRP-PD out of coverage users proactively maintain routes to the gateways. Furthermore, proposed protocols can be used in any heterogeneous scenario, combining a cellular network and WLANs operating in infrastructure or ad hoc (MANET) mode. We provide simulation results that demonstrate the effectiveness of the proposed integrated routing protocols and show the advantages and drawbacks of each gateway discovery approach in different heterogeneous scenarios.