> It's very similar to the token passing mechanism in the token > ring networks, isn't it? I am not familiar with the lowest level of TR, but IIRC it works differently. Also I used this scheme only for address resolution, after that it is more like a head-end topology. Wouter van Ooijen -- ------------------------------------------- Van Ooijen Technische Informatica: www.voti.nl consultancy, development, PICmicro products docent Hogeschool van Utrecht: www.voti.nl/hvu -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist