Sling that Data: Drupal from 30 miles away

Like a fresh cup of coffee with extra soy creamer, a daily morning trip to drupal.org to browse Drupal Planet or see recent activity helps to start the day off right. The current infrastructure issues not withstanding, if I have an internet connection I can get my open source blue alien fix. But what happens if I am a long way from an internet connection? Say, in the middle of a fishing village in rural Mexico or in the woods during a 24 hour bike race. In that case, you need to sling that data.

The general idea behind slinging data is that if you have a stable internet connection somewhere in the general area (within 20 or 30 miles) you can "sling" that data through a wifi bridge to your actual destination. At the ends of the bridge should be a pretty nice wifi antenna. We used 900MHz Yagi antennas which fold down nicely and are easy for transport. The antennas can be mounted on a number of things, but we choose (for ultra portability) to mount them to large wooden rods secured by christmas tree stands. The tricky party in setting this up is to make sure that both antennas point at each other. This is pretty easy if you are just shooting wifi within your immediate line of sight, but for longer connections (like between the chapter three office and the hills of berkeley across the bay) its probably best to use GPS coordinates to set up the connection.

Once you have two antennas pointing at each other, you need to attach the antennas to a couple of generic wireless routers. We used the trusted WRT54G routers with the detachable antennas and connected the routers to the antenna using some RF cabling we found online. On a software level, we immediately replaced the standard Linksys firmware with the industrial strength DD-WRT firmware created by Brainslayer. This allowed the power frequency to be boosted to 84 mW and the routers to be associated and placed into bridge mode (a built in option). Once they were powered on and associated, wow, bam, suprise, a wifi link was activated.

Of course, with that setup the wifi range is weak. Like 1 mile, maybe 2 miles. The real secret sauce is 4 W 915 L Series Antennafier. If you hook that amplifier on both ends of the connection, set its power to full, and start the bridge your wifi signal strength will dramatically increase. Over a two mile link, this setup was able to get a better connection than a normal a normal connection between the two wifi routers in the same room! Under optimal conditions (like in the desert or by from a boat on the ocean) this could send internet 30+ miles. Under non-ideal conditions, a your range will sadly be limited to 15 to 20 miles. So find some remote locations, invite some friends, and get your do fix on a boat, beach, or backyard.

Topics