Filtering Out Evil with Firewalls (part 3) - Manually Configuring a Firewall's Ports

Manually Configuring a Firewall's Ports

Sometimes adding a program to the firewall's Exceptions list, described in the preceding section, isn't enough. Specifically, some programs want you to open specific channels so they can chatter through them. These places are called ports.

You might come across a finicky program with special port requirements. For example, the World of Warcraft online game needs TCP protocol on port 3724 to be open for outbound TCP connections.

Here's how to tell Windows Vista's firewall to accommodate that pesky program:

1. Choose Control Panel from the Start menu.

   The Control Panel appears, listing its categories.

2. In the Security category, choose Allow a Program Through Windows Firewall.

   The Exceptions tab appears on the Windows Firewall Settings window .

3. Click the Add Port button.

   The Add a Port window appears, as shown in Figure 4 , ready for you to poke the required holes in your firewall.

   Figure 4: The Add a Port window lets you open a port on your PC for programs to communicate through.

   

4. Describe what you're doing in the Name box.

   This is for your own use so you can remember later why you're doing this. For instance, type Enabling Port 3724 for World of Warcraft.

5. Type the required port number in the Port Number box.

   Here's where you tell the firewall which ports to open; in the case of World of Warcraft, you want it to open 3724.

   Need to open several ports, or a range of ports? Enter every port number, separated by commas, like this: 3724,3725,3726,3728.

6. Click either the TCP or UDP radio button, and then click OK.

   World of Warcraft wants the TCP port changed, so click that radio button. The Add a Port dialog box now looks like Figure 5 .

   Figure 5: When filled out properly to open TCP port 3724, the Add a Port box looks like this.

   

7. Repeat these steps for any other ports that need to be opened.

   After you've opened the port required by your program, Windows Vista should allow the program to hold its conversations through the firewall.

• World of Warcraft isn't the only program with these special needs. You might find yourself changing ports for other online games and chat programs where it's important that the computer can accept communications that it didn't initiate. (Search the troublesome program's manual or help area for firewall to see which ports to open.)

• Internet file‐swapping programs also want certain ports open so they may communicate and share files. It's a drag, but check the program's fine print to see what ports it craves. Then add those ports to the firewall by following the steps in this section.