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Question: My firewall blocks CU-SeeMe! Help!

Answer: Firewalls are security screens erected by systems and network administrators to protect their users from unauthorized intrusions. A firewall can be configured to allow CU-SeeMe traffic through. A firewall screens out all traffic which it doesn't know about, and that includes the CU-SeeMe audio and video streams. Your firewall administrator can add filtering rules that explain to a firewall what CU-SeeMe traffic "looks like" by describing the ports it uses. The following filtering rules will allow CU-SeeMe UDP traffic through your firewall. Your firewall may use a slightly different syntax, but your firewall administrator will know what to do.

permit udp 0.0.0.0 255.255.255.255 xxx.xxx.xxx.xxx 0.0.0.0 eq 7648
permit udp 0.0.0.0 255.255.255.255 xxx.xxx.xxx.xxx 0.0.0.0 eq 7649
permit udp 0.0.0.0 255.255.255.255 xxx.xxx.xxx.xxx 0.0.0.0 eq 7650
permit udp 0.0.0.0 255.255.255.255 xxx.xxx.xxx.xxx 0.0.0.0 eq 7651
permit udp 0.0.0.0 255.255.255.255 xxx.xxx.xxx.xxx 0.0.0.0 eq 7652

Replacing the xxx.xxx.xxx.xxx with the address of your computer will allow CU-SeeMe traffic only to and from your computer, everyone else on your network will be unable to use CU-SeeMe. Replacing it with a broadcast address will allow everyone on your network to use CU-SeeMe. The safest arrangement allows CU-SeeMe traffic to a computer that's not connected to your remaining network, or one protected by a router that's properly-configured to provide very tight network security.