Originally Posted by jcresq

Here is an excerpt from Wayport's FAQ. I may have mischaracterized it:

Does Wayport block any specific types of traffic?

Due to the proliferation of viruses, worms and other malicious activity on the Internet, we block specific ports to increase the security of our network. Specifically, TCP traffic is blocked on ports 80 (inbound), 135 (inbound), 137, 138, 139, 445 and 8053. UDP traffic is blocked on ports 1434, 8053, 8083 and 8084. We regularly update our firewalls to address new and pressing security issues.