Sunlight Labs, known for opening America’s government, had a problem when they recently moved facilities. Creating new keys for team members was becoming costly, so they figured out an alternative method of providing secure access using a WRT54GL, easily sourced components, and a trusty copy of Make: Electronics. [Thanks, Nicko!]

With the firmware installed, I was able to SSH into the router and perform some simple manipulations of the system’s GPIOs — General Purpose Input/Outputs. These connect to things like the system’s LEDs and switches, and can be controlled in software. I selected a GPIO that didn’t seem to be used by OpenWRT — it illuminates the “DMZ” LED on the front panel — and wrote a very simple script to control it. I could now flip a tiny light on and off from a network connection.

In the Maker Shed:

Make: Electronics
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