Entirely agreed. On the other hand I have what is turning out to be a unique (here) point of view about this. I don't want to prevent this kind of theft -- I want to discover it, and remove perpetrators from any IXP where they try it. I don't want to block it. I want to ensure that it is never tried twice. I appear to be in the minority wrt this view. This is a great idea. But do you have any idea how much expert engineer time is involved in tracking down theft of this sort? Most of our employers would much rather spend that resource on tackling the big problems. If you can get the tools (simply having the IXP switch keep a port-to-port traffic matrix would help a lot...), I suspect you'd find a lot of converts to your "minority" view - many would prefer to expose and ostracize the perpatrators of these thefts instead of ignoring them. --Vince