In this paper, we study how to adapt the routing according to dynamic network conditions in wireless ad hoc networks. We present a method that dynamically chooses routing agent between ad hoc on-demand distance vector routing protocol (AODV) with TCP (endto-end transport) and delay-tolerant networking (DTN) routing and bundle protocol (hop-by-hop transport). We use simulations to confirm that DTN routing and the bundle protocol leads to significantly shorter end-to-end delays and higher message delivery ratios than AODV and end-to-end TCP when the wireless node density is low. However, with high node density, DTN routing, especially epidemic routing, suffers from multiple bundle copies and simultaneous transmissions that lead into collisions and retransmissions at the wireless link (MAC) layer. Thus, we propose a simple adaptive scheme that uses only local information to transmit the messages from source to destination using either AODV or DTN routing, depending on current node density, message size, and path length to destination.
Another hybrid scheme that combines AODV and DTN routing is presented in REF .
Adaptive routing in mobile opportunistic networks
MSWIM '10
Computer Science