I don't know why it's so amusing, but the network stack is fully functional for loopback. Fire up telnetd, and telnet back to yourself. telnetd -l /bin/sh -p 2

I don't know why it's so amusing, but the network stack is fully functional for loopback. Fire up telnetd, and telnet back to yourself. telnetd -l /bin/sh -p 23 telnet 127.0.0.1 23 plenty of other services: httpd.. what a hoot.