How does Skype manage to connect without setting the required proxy

Question

The situation is as follows: I'm at college and we have to set manual TCP/IP V4 settings, and a proxy to be able to connect to the internet. however.. skype manages to connect and fully work even before i've entered the proxy settings

my question is, how does the Skype application do this?. because i'd like to write a program that uses that method to connect without proxy.

Answer 1

Presumably, it doesn't use HTTP, or operate on HTTP ports, so it doesn't need to use the proxy because the network isn't configured to block it.