I think it is a step in the right direction. Honestly though, I know myself and I would ignore that popup as an ad. Perhaps being able to call and confirm instead of clicking a link. Show the phone # and confirmation code in that ad.
I like the idea of walling off users if and ONLY if there is a very low chance of false positives and only if a person can get the restriction lifted quickly.
I have been saying for a long time that ISP's could not only save themselves bandwidth by proactively stopping botnets, they could also help the Net in general.--
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