squid and unauthorized clients rate-blocking

["Eugene M. Zheganin" <emz@xxxxxxxxxxxxx>]

Hi.

I use squid mostly for internet access authorization in corporate 
network. I have a problem. Let's suppose some foobar company has 
developed a proxy-unaware update mechanism using HTTP to update their 
software. Or some internet company wrote a javascript that does execute 
outside proxy context in a browser. Such things can produce a massive 
amount of GET requests which squid answers with HTTP/407. Massive like 
thousands per seconds from just one machine. In the same time, being 
explicitly blocked with HTTP/403 answers, this madness stops. So, is 
there a mechanism that I could use for, like, send 403 after exceeding 
some rate to a client ? Or rate-block some acls ? Or something similar ? 
Because right now I just block these machines using a packet filter, 
because this entire thing just eats my CPUs.

Thanks.
Eugene.