Trajectory and Buffer Aware Message Forwarding for Multiple Cooperating UAVs in Message Ferry Networks

This paper presents a Trajectory and Buffer Aware message Forwarding (TaBAF) scheme in message ferry networks with multiple mobility-controlled UAVs. UAVs are basically message ferries with an on-the-fly mobility decision maker to deliver messages between isolated nodes. Besides, UAVs forward messages opportunistically when they visit each other on-the-air. UAVs have only local observation in our network model and do a signaling with each other when they fly into the radio transmission range of each other. The signaling information are the next node that a UAV will visit and its buffer state. TaBAF applies this information in its message forwarding decision and forwards a message to a neighbor UAV if it can deliver the message earlier. The results show that the TaBAF in message ferry networks outperforms pure message ferry approaches and existing message forwarding schemes in terms of end to end message latency. We showed that the TaBAF decreases the average traveling delay of messages in UAVs and this is the reason for its performance improvement. Moreover, TaBAF decreases average flied distance of each UAV in the network by efficient message forwarding.