Squid (and probably others) can filter accesses based on the user agent. Some network firewall (as opposed to personal ones) can be configured to filter accesses based on the user agent header.
As you know, every peace of software trying to access internet through a proxy advertise its flavour using the user agent header, and the user agent header is very hard to spoof :-) Never heard of studip answers on mailinglists, did you? :-) > >> Zone alarm and other Windows based Software Firewalls can block > >> network access for programs. > >> A HW firewall can only block a whole machine but can't denied access for one > >> software > > Never heard about proxies, did you? :-) > If proxies can now distinguish which program redirects via them, I > would be interested to hear how... _______________________________________________ Full-Disclosure - We believe in it. Charter: http://lists.netsys.com/full-disclosure-charter.html
