A localization process in a network of source devices and sink devices on a 1394 bus, is performed by a source device while it is communicating to a sink device, which determines local network links from nonlocal ones. An actual round trip time calculation is performed only by the source device and the sink device can be relatively passive. The duties of the sink device are performed in hardware and involve (trivially) modifying the received message while moving the message from the input isochronous channel buffer to the output isochronous channel buffer.