The only thing I don't like about the PIX is that it is not completely secure, it can only authenticate FTP, HTTP, and Telnet protocols. It will not authenticate HTTPS protocol, so when attempting to make a secure HTTPS connection through the firewall, you first must authenticate using HTTP (which causes the user/pass to be transmited in clear text) and then start a secure connection. This leaves the possibility of allowing unwanted users behind the firewall.