[squid-users] auto blacklist users

Hello.

[sorry, slightly off topic]

I'm the ICT technician of a school. I have squid running to make the most
of our bandwidth. Our ISP provides some content blocking but this is
proving ineffective against the proliferation of proxy sites.

I've started to monitor and block sites with squid ACLs. This is also not
so effective as there are 1200 users looking for new sites and only 1 user
trying to block them.

Since there is no punishment for hitting any DENY ACL there's no reason
for them to stop.

What I need is to apply some back pressure, i.e. automatically block
persistant offenders.

Does anyone have anything like this?

N.B. This has to be user based. Host/IP based will not work due to the
hot seating.

Thanks

-- 
ian j hart