DIY Wifi Bridging with DD-WRT

As the number of networked devices in our home has increased in the past few years, I’ve developed a problem that I suspect many of you share: the kudzu-like proliferation of ethernet cables. Sure, wireless connections are a huge help, but there always seems to be at least one stubborn machine that sprouts an annoying CAT-5 cable. And naturally, this evil tentacle invariably ends up strung across the most unsightly and inconvenient location possible.

In our most-recent case, the offending device was an XBox 360. Newer 360s include built-in wifi, but ours was an older, cheaper model that possessed no such functionality. We struggled along for a while with an ethernet cable strung across the floor like a trip-wire, until the inevitable near-disaster occurred and a better solution was required.

The obvious solution to the trip-wire problem is some sort of wireless network adapter. Microsoft markets an official wireless adapter for the 360, as does MadCatz, TrendNet, and other manufacturers. If you’re interested in the most hassle-free solution to cable clutter, then I highly recommend one of those adapters. On the other hand, if you are looking for a less expensive and more Do-It-Yourself solution, then you might consider what I did, which was to repurpose another wifi router as a bridge.

I happened to have a spare wifi router kicking around, and this seemed like a good opportunity to put it back into use. I knew that it was possible to use a secondary router to bridge to our main wireless access point, but the manufacturer’s stock firmware did not support such functionality; fortunately, we live in a hardware-hacking, open source kind of world, and there are alternatives to the manufacturer’s firmware.

DD-WRT is a third-party firmware designed as an upgrade for the limited firmware included in most consumer-level routers. You may not be aware of it, but a wireless router is actually a small computer, and the software it runs is called firmware. Among other things, this firmware configures all the network hardware in the router, acts as a web server to support browser-based configuration of the router, and implements security controls for your network. This firmware can be upgraded to correct any bugs or to add new functionality, much as you might install upgraded software on a standard computer. Firmware upgrades are traditionally provided by the router manufacturer, but there are also upgrades available from third-party sources such as the DD-WRT team.

The DD-WRT wireless configuration screen

The instructions for installing DD-WRT may seem a little daunting at first, but it essentially boils down to this:

Connect a computer to the router with an ethernet cable
Set up a static IP on your computer
Perform a hard reset of the router
Upload the new DD-WRT firmware to the router
Wait for the router upgrade to complete
Reset the router once more
Configure the router for Client Bridge mode

Once the secondary router was upgraded and configured for Client-Bridge mode, I moved it into place next to the XBox, connected the two, and hit the power button. A quick network test confirmed that everything was working perfectly, in cable-free glory. Goodbye ethernet kudzu!

As mentioned above, there are several hardware solutions to this sort of problem, all of which are essentially plug-and-play. If you are at all nervous about messing around with firmware or have more money than time on your hands, then I definitely recommend one of the pre-packaged solutions. On the other hand, if you like to tinker, then give DD-WRT a try.

So, assuming you are feeling adventurous, here are some useful links:

DD-WRT Home Page

DD-WRT Supported Routers

DD-WRT Wiki (installation info and more)

DD-WRT WDS Information (an alternative bridge solution if your primary router is already running DD-WRT)

Tomato, another third-party firmware