Receiver Oriented Trajectory Based Forwarding

Trajectory Based Forwarding (TBF) is a new approach to routing in ad hoc wireless networks. It exploits node position information and, similarly to source routing, requires the source node to encode a trajectory into the packet header. The routing process does not require to specify forwarding nodes. As a matter of fact, forwarding nodes are dynamically selected while packets cross the network according to their position with respect to the trajectory. Therefore, this new approach is particularly suitable for application scenarios where network topology is fast varying, due to node mobility (e.g. inter-vehicular networks) or to energy management schemes (e.g. sensor networks), whereas the stability of the trajectories is guaranteed by the physical characteristics of the service area (roads, building aisles, etc.). This paper describes a new TBF scheme that shifts forwarding decision from transmitter to receiver exploiting broadcast transmissions. We thoroughly analyze the behavior and the properties of the proposed scheme considering the impact of the medium access control mechanism and the effect of limited transmission ranges. We consider piecewise lines connecting source node to destination area and we extend the approach to the multicast case by defining trajectory-trees. Moreover, we propose a forwarding mechanism able to walk around obstacles along the trajectory.