Paul Vixie wrote:
2. Filter aggressively. Run a dark-net, and if one of your customers hits it, blackhole their /32 for both inbound and outbound traffic, flag their record in your customer database, and wait for them to call. When they call, give them a list of anti-virus products for their 'puter, and the phone numbers (yes, sorry, no web access for them at the moment) of some vendors. This will cost you some top line revenue, but save your margins.
This can be automated to a level where the customer is redirected to a self-service portal allowing him/her to clean up the PC (if at all possible) and after that has been done the connectivity is restored. Saves your helpdesk a call and helps the margins further. (although the productized solution costs some, but the net effect is still the same) Pete