Thanks, all for the replies. As has been surmised, I'm using NetworkManager. So next time the cable modem needs to be rebooted, I'll try sudo /etc/init.d/network-manager restart and see if that reestablishes a connection. I gather I don't need to use NetworkManager---this is on a desktop PC with a ethernet connection, no wireless, etc. However, for the nonce I'll leave well enough alone. Joe