Automatic shutdown of infected network connections

Sat Aug 30 01:44:11 UTC 2003

Some universities such as Vanderbilt University are automatically
shutting down network ports when they detected signature worm traffic.
Almost 25% of the students' computers were detected as infected when they
connected to the university network.

http://www.vanderbilthustler.com/vnews/display.v/ART/2003/08/29/3f4eb4b3537e0

How many ISPs disconnect infected computers from the network?  Do you
leave them connected because they are paying customers, and how else
could they download the patch from microsoft?