Your DSL connection may connect to a hub rather than a switch on the other side of the DSLAM, in which case the IP traffic would be echoed to all ports. That would be very, very strange though. It would also generate a huge amount of traffic if there are many other people in your area using DSL. It could be that there's so much traffic through the switch on your ISPs side that it actually floods the ARP cache and it briefly reverts to "hub mode". That would also be very weird.
Last edited by chort; 08-29-2004 at 03:45 AM.