A method of operating a communication network having multiple stations, each able to transmit and receive data, so that the network can transmit a message from an originating station to a destination station via at least one opportunistically selected intermediate station. Stations wishing to transmit data transmit probe signals which are responded to by other stations, thereby to identify available stations. When a station has data to send, it transmits probe signals with Request to Send messages, identifying the data to be sent. When a station receives such data for onward transmission, it transmits its own probe signals with a Request to Send message and including identification information relating to the data. The Request to Send messages are received by other stations in the vicinity, so that they serve as an implied acknowledgement of the receipt of the data by the forwarding station without the need for sending explicit confirmation.