Hi all, I have come up with a diagrammatic version of Freek's Ethernet use case. Perhaps we can discuss on this call? Guy ------------------------------------------------------------------------------------------------------------------ Guy Roberts, Ph.D Network Engineering & Planning DANTE - www.dante.net<http://www.dante.net/> Tel: +44 (0)1223 371 316 City House, 126-130 Hills Road Cambridge, CB2 1PQ, UK ------------------------------------------------------------------------------------------------------------------