Just wondering, but how would I provide direct communications paths between 2 pcs using the TCP/IP port level? If I am using a program or game (any number of which) to make a server and want to allow a specific person access to something I am running through my Linksys router.... better example; Say home world 2 or Diablo, or Starcraft or whatever. If I want to allow someone else access (once the program has established it is waiting for another computer to connect), would this work?
Person B entering the network enters at 192.168.10.200:16200. Providing I have set my router to keep open port range of START= 16200 to END = 16201 and 192.168.10.200? I know there are a ton of variables I am leaving out but, in simple form the key here is Start to End = : to match. Right? Or do they have nothing in common at all?
In other words, what does the ":16200" stand for?

Mod Edit: Topic moved to more appropriate forum~ TMacK <--- sorry bout that

If both PC's are on the local side of the router there is no need
to forward anything. If the player is outside the network then you
need to forward the port (16200) to the machine serving the game.

Example:
I have server A running Americas Army. (192.168.2.2)
I have desktop B with the game. (192.168.2.3)
In game I just: Open 192.168.2.2:16200 ( or whatever port the game listens on)
If I want someone else to join they need to enter my public IP (172.6.111.222:16200) and
have my router forwarding requests on port 16200 to the server (192.168.2.2)

Your router manufacturer will usually have this info on their site.

You da man Raw!

How do you know what port they enter from (16200), and how did you get it to work? I'd like to know, so I could play Diablo II with my girlfriend on tcp/ip over the internet. Please let me know how to make it work. Thanks