Patent ID: 8462691

Claim:
A method of operating an opportunistic relaying network comprising at least one network access point, and a plurality of mobile wireless data relay devices each having a buffer for storing data messages, whether own-generated or received, such stored data messages being referred to hereafter as payload data, the method comprising: at a source one of said devices having payload data to be relayed to a network access point, the network access point being out of range of the source device, (a) transmitting a request to transmit (RTS), in respect of payload data; (b) receiving, from each said device within range of the source device and responding to the transmitted RTS, respective device-related status data comprising an indication of its buffer vacancy; (c) selecting in accordance with an opportunistic routing algorithm, a responding device to receive payload data; (d) setting the period of a retransmission timer to be a minimum value multiplied by an inverse function of the buffer vacancy of the selected device; (e) transmitting payload data to the selected device; (f) triggering, upon that transmission, the retransmission timer; and (g) upon expiry of the retransmission timer period, repeating steps (a) to (f) in respect of any transmitted payload data for which acknowledgment generated by a network access point has not been received.