The server hosting this blog respond on all ipv4 TCP ports from 1 to 65535.
The following URLs should also work if you are not filtered :
This allows you to test what TCP ports are filtered by your local network.
Command line example with netcat:
$ nc -v portquiz.net 1 Connection to portquiz.net 1 port [tcp/http-alt] succeeded! $ nc -v -w2 portquiz.net 65535 nc: connect to portquiz.net port 65535 (tcp) timed out: Operation now in progress