How to: Build a Wireless Bridge Using DD-WRT, Part II - Page 2

Bridging multiple clients

In the olden days, configuring a wireless router as a wireless bridge limited you to one attached client. You may run across this information on the Internet, but in the current release of DD-WRT (V24 SP1), I have found no problem using multiple clients simultaneously—either wired or wirelessly—in any of the four modes discussed in this article.

Administering your secondary router

Some people have had the problem where, once their secondary router has successfully created a bridge, they no longer know how to contact it to reach the administration page.

In either client bridge or repeater bridge mode, your connected machines are now on the LAN with your primary router. It is important that your secondary router’s own internal network be on this LAN, too. This is why, on the figure configuration page illustrated earlier, we take care in setting the “LAN IP Address” sensibly.

So, if you are using a bridge mode and your primary router is 192.168.1.1, and you’ve assigned 192.168.1.2 to your secondary router, you should not have a problem logging into either router using their respective IP address.

But if you are using a bridge mode and your secondary router is set to 192.168.0.1, while your primary router is 192.168.1.1, you may be online just fine, but will no longer be able to log into the secondary router. So don’t do this.

Remote administration

For security reasons, most routers do not let you log into the administration interface from outside the LAN. However, many routers include an option to enable remote administration, which can be convenient, say, to access your home router from your office, or to provide support to friends and family elsewhere.

One question that arises with client bridges and repeaters is how to access the secondary router remotely. Your primary router has an Internet-accessible IP address, but your secondary router does not. Whether in a bridged or non-bridged mode, your secondary router has an IP address for a private LAN.

In either client bridge or repeater bridge mode, you do not need to enable remote administration on the secondary router. Rather, you need to setup “port forwarding” on your primary router to forward from a chosen port to your secondary router at port 80.

Port forwarding configurations vary widely between routers, so consult the manual or other online instructions for your primary router. But the principle is common to all: configure a port forwarding rule so that incoming requests from the Internet to, say, port 81 (or any unused port) are redirected to the LAN IP of your secondary router on port 80.

In either client or repeater modes (non-bridged), you do need to enable remote administration on your secondary router. The port forwarding configuration would be the same—the difference is that your secondary router will see these requests coming from a separate LAN (the primary router), which it will reject unless remote administration is enabled.

Ask the Wi-Fi Guru

Hopefully this article sheds more light on the confusing area of wireless bridges, clients, and repeaters. As always, if you have questions related to this topic or anything to do with home and small business wireless LANs, click on the byline above to send the Guru a query. You can also post questions or comments in the Comments field below.

Additional Resources:

• DD-WRT Tutorial 1: Static DHCP

• DD-WRT Tutorial 3: Building a Wireless Bridge

• DD-WRT Tutorial 4: Defining Priorities with QoS

• DD-WRT Tutorial 5: Wireless Repeater

• How to: Install DD-WRT (X86) On a PC

Aaron Weiss is a freelance writer, editor, and Wi-Fi enthusiast based in upstate New York.  Click here to read last month's Wi-Fi Guru column.