Dflood network protocol over commercial modems

This paper presents the integration of the underwater communication network protocol “Dflood”, of the restricted flooding family, over commercial modems from Teledyne Benthos. The network protocol was re-implemented and is running on a separate processor board, communicating with the modem over the serial port. Issues of fragmentation and packet reception errors are handled by a separate framing mechanism between the network layer and the modem. The setup was successfully tested in November 2017 as part of the DUSN (Distributed Underwater Sensor Networks) cooperation project between Canada, Norway, and Sweden. Good network layer performance was achieved in spite of most individual links having a packet delivery ratio between 0.25 and 0.75. By this work, we show an example of how network protocols from the research community can be run over commercial modems without accessing or modifying the modem firmware.