[squid-users] DoS using Squid

I have faced a problem where a client request to some .mpg and .avi sites
keeps coming again and again. Something like a person sitting at the other
end doing a Refresh for a 4 MB file.

This turns out to eat my incoming bandwidth and rest of the users are
affected.

Disconnecting the client physically from the network does the job but is
there a better solution (apart from EULA :)).

I found it out that multiple client side active requests for the same uri as
well.

Any help is appreciated