Before I begin, let me just say that I am not the authority on this! So if you see any incorrect information, please correct me.
STEP 1:
FIrst, you'll need to find the address for your Router, and the IP Address for your computer. The way to find these numbers is different depending on whether you have a Mac (step 2A) or a PC (step 2B).
STEP 2A:
If you have a Mac, here's how to find the IP Address and Router Address:
-Open up "System Preferences".
-Click on "Network".
-Click on "Configure".
-Click on "TCP/IP".
-Listed you should see your IP Address and your Router Address.
Here are examples of what the numbers should look like:
IP Address (just an example!):
192.168.1.7
Router Address (just an example!):
192.168.1.1
STEP 2B:
If you have a PC, here's how to find the IP Address and Router Address:
-Go to the start menu and select "Run".
-In the dialog box, type in "cmd" (if that doesn't work, try "command"). This should open up a DOS window.
-Type in "ipconfig" (if that doesn't work, try "winipcfg"). This should bring up a window titled "Windows IP Configuration". Listed, you should see your computer's IP Address, and also the Default Gateway, which is the Router Address.
Here are examples of what the numbers should look like:
IP Address (just an example!):
192.168.1.7
Router Address (just an example!):
192.168.1.1
STEP 3:
Access the Settings to your Router
Open up your web browser and type the Router Address into the URL location (for example -- http://192.168.1.1/). If you typed in the correct number you will be prompted to enter in a username and password. By default, the username is "admin", and the password is also "admin". Type these in unless you've changed the default names. On a side note, you should probably change these if you have a wireless router to prevent random people from accessing your internet connection, otherwise you may have unnecessary lag in your network game. If you have trouble gaining access to your router, you will have to contact the manufacturer for your router -- not the manufacturer of your modem or service provider.
STEP 4:
Open Port 4226
This last step may be difficult because every router has a different way of changing the settings. So I can't explain exactly how to do this -- I can only give you the general idea. You'll have to figure out the rest.
-You'll need to find a section called something like "Applications", or "Games", or "Port Forwarding".
-Type in 4226 for both TCP and UDP. If there is a checkbox for "both" TCP and UDP, select it so you don't have to type in 4226 twice. If there's a start and finish for the port range, type in 4226 for both.
-Under IP Address, type in your computer's IP Address (NOT THE ROUTER ADDRESS!).
-There should also be an option to type in the name of the application that the port will be opened for. It doesn't matter what you type here, so just type in "MARATHN" OR "ALEPH1" to keep things organized.
-Remember to save your settings before exiting.
That's it. You're ready to gather network games in Aleph One/Marathon!
TROUBLE SHOOTING
If you're still having problems, here are some troubleshooting tips that may help:
-Make sure you have the current version of Aleph One.
-For the first games you gather, use Marathon Infinity since that's what most people are using.
-Sometimes your computer's IP address can change! So if you can't gather a game, the first thing to do is check to see what your computer's current IP Address is, then make sure that same number is entered into your Router's settings (for port 4226).
-To play online network games, you'll need all of your internet connection's power. A slight change in speed can mean the difference between a smooth network game and one that is riddled with lag. So make sure you're not downloading or uploading in any other applications. Make sure your roommates (or whoever lives with you) aren't downloading or uploading anything. If you have a wireless router, make sure you've secured access to the router so outsiders can't access it.
-You can test your connection speed using the following method:
Windows: Go to the Start Menu and select Run. Type in "cmd". Then type in "ping google.com -n 10". Look at your average ms to see how you're doing. This can be useful in determining whether or not your connection is what's causing lag in a network game, or whether or not conditions for gathering a smooth running network game are present.
Macintosh: Open the Terminal application. Type "ping -c 10 google.com", then press return.
-You can also test your connection speed at:
http://pingtest.net/
And I'm told these methods of testing aren't as accurate, but here they are anyway:
http://www.speedtest.net/
http://www.speakeasy.net/speedtest/
-Generally speaking, the more players in a game, the more lag there will be. So you may need to limit the number of players in your game, or increase the latency tolerance (listed under "Network" when gathering a game). Distance also plays a factor, so the further away the person you're playing is located, the more lag you will experience. Someone very far away with a slow connection can make the game slow for everyone.
TIPS
-Hold alt+enter (or option+enter) to shrink the screen in Aleph One. This allows you to do other things while running Aleph One. I would only advise doing this while in the chat screen, not the actual game.
-Type ".available" to see who is available to join your game. This is useful when you're gathering a game and otherwise wouldn't be able to see who is using Aleph One. You can also type ".who" to see everyone who is there.
-Type in ".afk" to gray out your name if you are away from the keyboard. As soon as you type something your afk status will be taken away. Or to return, you can type ".back".
-Type ".help" or ".help2" to see other dot commands. There was also a more detailed post regarding dot commands here on the pfhorums.
-In the middle of the game, press the "1" key to see other people's connection speeds. The higher the number, the slower the player's connection. Any ping under 100 is ideal.
That concludes my lengthy tutorial and tips. I'm sure this topic has already been tackled here on the pfhorums, but I just wanted to post something I could use to quickly refer non-hosters to. If this post is successful, it will increase the number of players that can host.
EDITS:
6/3/2011
- Corrected latency tolerance tip and added http://pingtest.net/ (thanks, Treellama!).
- Corrected latency tolerance instructions to correspond with the current version of Aleph One.
- Updated the method for checking pings to match the method used in the latest version of Aleph One (press "1" instead of typing ".ping").
- Added http://www.speedtest.net/ as an alternative for testing connection speeds (thanks, Red Fox!).
- Added the Macintosh method for checking connection (thanks, g pack!).
- Used more minor re-formatting to organize guide.
- Deleted title from the top of the post (it was redundant).
- Updated Step 2B to include "cmd" and "ipconfig".
- Updated the title of the window in Step 2B.
- Included an alternate method of checking connection (thanks, W'rkncacnter!).
- Corrected some glitchy punctuation.
- Used some minor re-formatting to organize the guide.
