For anyone who wants a pointer:

Take a close look at the UDP traffic and see what it is missing that the TCP traffic has. Also, consider what is in the payload of the packets. Once you get this, consider why and what the purpose may be. This should get you on your way.

Of course you can read the results that are on the page (like mentioned above).

I did participate but I did not get mentioned :-(
Oh well, there is always next time.