Patent attributes
Messages on controller area network (CAN) buses are communicated over subsea links. Repeaters couple CAN buses to each end of a subsea link. The subsea link may be, for example, a twisted pair or a single wire with a sea ground. The repeater detects a direction of transmission, that is, whether a signal began on the CAN bus coupled to the repeater or on the subsea link coupled to the repeater. Signals from the CAN bus are conditionally transmitted to the subsea link depending on the detected direction of transmission. Signals from the subsea link are conditionally transmitted to the CAN bus depending on the detected direction of transmission. The repeater can operate at the physical layer without analyzing contents of the CAN bus communications.