Quote from the NetHelp.txt
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GameSpy, Internet Play, and Shared Internet Connections
If you are having difficulty creating or joining games, or if
other people are unable to join your GameSpy or Internet game,
then you may get better results after adjusting your network
configuration. There are two aspects to this, NAT
(network address translator) devices, and firewalls.
A NAT is usually a router or switch which permits multiple
home computers to share a single cable or DSL modem
connection on a single IP address. NAT devices work by
making your internally known IP address (that is, the address
you are known by on your home network) be different from your
externally known IP address (the address that you are known
by on the public internet.) This usually means that other
people are unable to see games that you create. Your NAT,
router or swtich should provide a way to set up a single
computer as a "DMZ host". See your NAT, router or switches
manual for more details. Some NAT's may also prevent you
from joining a game. Again, setting up your computer as
the "DMZ host" for the network should help.
Moving your system to become the "DMZ host" will make
it more exposed to the internet and at a potential risk for
security. It is recommended that you consult with your ISP
or network administrator before making this change.
A firewall blocks other computers on the internet from
contacting your computer through various IP port ranges.
Many NAT's switches and routers may have a firewall built in.
This assists with securing your home or corporate network.
If the ports required to play Star Trek: Armada II
are blocked, you will be unable to create a game, and you
may be unable to join a game. You will need to ensure that
the GameSpy and DirectPlay 8 ports are permitted through
your firewall. The required ports follow:
Firewalls are designed to provide security to your system
or network. Activision is not responsible for any issues
that arise from modifying your security. It is recommended
you contact your ISP or network administrator before making
any changes to your firewall.
DirectPlay 8 Ports
2300..2400 UDP inbound and outbound
6073 &nsbp; &nsbp; &nsbp; &nsbp; TCP inbound and outbound
GameSpy Ports
80 &nsbp; &nsbp; &nsbp; &nsbp; TCP, outbound
6500 &nsbp; &nsbp; UDP, inbound
6667 &nsbp; &nsbp; TCP, outbound
13139 UDP, inbound and outbound
27900 UDP, inbound and outbound
28900 TCP, outbound
29900 TCP, outbound
29901 TCP, outbound