G-AODV+PCMTAG: routing in manet with low overhead flooding and route-shortening

In an ad-hoc routing protocol based on flooding of a route request control message such as AODV and DSR, all reachable mobile computers are required to broadcast the message. Especially in a high density ad-hoc network, a broadcast storm causes higher battery consumption and lower connectivity. This paper proposes G-AODV routing protocol which is a group-based extension of AODV where only mobile computers belonging to the same group as a source one are engaged in flooding of a route request control message. Due to the group based flooding of the message, connectivity gets lower and detected transmission routes get longer. This paper proposes dynamically determined equivalence between two groups based on density of neighbor mobile computers. In addition, in order to reduce the length of a message transmission route, PCMTAG (Passive Contribution for Message Transmission in Another Group) is also proposed. Here, a mobile computer in another group is engaged in message transmission only when it provides a shorter message transmission route without or with limited additional control messages. Simulation experiments show that G-AODV and PCMTAG requires 31.7% less control messages, 4.5% longer route detection time and 0.1% lower connectivity to achieve 9.6% shorter transmission route than AODV.