Neil monitors his firewall rules and log files closely on a regular basis. Some of the users have complained to Neil that there are a few employees who are visiting offensive web sites during work hours, without consideration for others. Neil knows that he has an updated content filtering system and that such access should not be authorized.

What type of technique might be used by these offenders to access the Internet without restriction?

A.
They are using UDP which is always authorized at the firewall.

B.
They are using tunneling software which allows them to communicate with protocols in a way it was not intended.

C.
They have been able to compromise the firewall, modify the rules, and give themselves proper access.

D.
They are using an older version of Internet Explorer that allows them to bypass the proxy server.

Explanation:
This can be accomplished by, for example, tunneling the http traffic over SSH if you have a SSH server answering to your connection, you enable dynamic forwarding in the ssh client and configure Internet Explorer to use a SOCKS Proxy for network traffic.