I thought that somehow Foxboro maps the MAC address to the letterbug in addition to the IP address. Most of the stuff on the nodebus isn't using IP addresses, but MAC addresses (or so it would seem if you run a packet sniffer). How they map the addresses to the letterbugs, I do not know. Good Luck, David "The only reason for time, is so that everything doesn't happen at once." Buckaroo Banzai _______________________________________________________________________ This mailing list is neither sponsored nor endorsed by Invensys Process Systems (formerly The Foxboro Company). Use the info you obtain here at your own risks. Read http://www.thecassandraproject.org/disclaimer.html foxboro mailing list: //www.freelists.org/list/foxboro to subscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=join to unsubscribe: mailto:foxboro-request@xxxxxxxxxxxxx?subject=leave