Indeed! It will be fun to see that code. Why? Once 10M Ethernet hardware was available, people switched pretty rapidly to using that, instead of the CHAOS hardware. (It was available off the shelf, and the analog hardware was better designed.) That's part of the reason ARP is multi-protocol. Some hard-to-run cables (e.g. under the street from Tech Sq to main campus) stayed CHAOS hardware because it was easier to just keep using what was there, but most new machines got Ethernet cards. Noel