Geo-based inter-domain routing (GIDR) protocol for MANETs

Inter-domain routing for MANETs (mobile ad hoc networks) draws increasing attention because of military and vehicular applications. The existing border gateway protocol (BGP) is the de facto inter-domain routing protocol for the Internet. But BGP is not applicable to MANETs because the BGP design is based on a static Internet which does not support dynamic discovery of members, and cannot scale to mobile, dynamic topology environments. The proposed geo-based inter-domain routing (GIDR) protocol obtains efficient communications among MANETs and achieves scalability in large networks by using geo-routing packet forwarding scheme and clustering technique. The basic structure of GIDR is clusters in each domain. The distributed clustering algorithm elects within each domain a cluster head (CH). The cluster head in the subnet acts as local DNS for own cluster and also (redundantly) for neighbor clusters. The cluster head advertises to neighbors and the rest of the network its connectivity, members, and domain information. The advertising protocol plays the role of BG Protocol. Geo-routing is the main packet forwarding scheme in GIDR. Assuming that all nodes are equipped with GPS, greedy forwarding is a straightforward routing scheme and can be easily standardized and implemented in all "coalition" nodes. Moreover, it is inherently scalable and is "address" independent (thus, it works across domain boundaries). If greedy forwarding fails, the packet is "directionally" forwarded to the "most promising" node along the advertised direction, i.e., direction forwarding. The experiments have shown that the proposed inter-domain routing has achieved scalability and robustness to mobility. The simulation results with airborne backbone network, an important application domain in military, as one of the domains are also presented in the paper.