The LHC includes a 27-kilometer circular tunnel 50 to 175 meters below the surface near Geneva, Switzerland, plus an underground lab the size of a small village, as well as fantastically complex and delicate detectors -- some as big as small office blocks and weighing hundreds of tons.

In the experiments, slated to begin later this year, beams of protons or heavy ions rotating around the LHC tunnel in opposite directions at close to the speed of light will collide, smashing into smaller constituents – hadrons, electrons, muons, photons. The detectors will measure the results.

The object? To recreate conditions a fraction of a second after the Big Bang that scientists believe created the universe billions of years ago, to try and work out what happened -- and also to study high-energy particle interactions and, just maybe, observe new particles and phases of matter, including the basic building blocks of the material world.

This facility is riddled with Wi-Fi networks, an estimated 300 access points in all, most from Proxim Wireless. Not only do the number of APs mean that interference is a major problem, but much of the scientific equipment also interferes. Which is why CERN’s network gurus have turned to Wi-Fi mesh technology for a number of applications, including one mind-boggling maneuver during site construction.

The requirement was to move the huge detector for the ATLAS experiment – the size of a five-story building – from the surface down a 100-meter shaft to the lab. The trick was that the incredibly fragile detector could not tilt or absorb vibration, even a tiny bit. That meant that the crane lowering it had to be controlled very precisely, based on feedback on the detector’s progress down the shaft.

The solution the project team came up with involved a unique Wi-Fi mesh network that would relay data from sensors on the detector to computers that engineers could use to calculate adjustments in crane controls, which would guide the operator.

Using mesh technology was vital for a couple of reasons, says Olaf van der Vossen, the engineer responsible for network infrastructure at CERN. One is the ability -- with dual-radio mesh access points -- to switch between using 2.4GHz and 5.8GHz spectrum to avoid interference, and the ability of the network to dynamically reroute data when the path between two access points becomes “polluted” with interference. Another crucial benefit was ease of setup.

Click Here to Continue Reading the Full Article