Trenching is the name given to the methods used to lay the pipes for fiber-optic cables, whereby narrow slits are milled in the ground and asphalt. Up until now, 300 meters of cable took around one day to lay. With the help of the technology from Austrian company Layjet Micro-Rohr , based in Ebersdorf in Styria, Deutsche Telekom now wants to increase this capacity to up to three kilometers a day. The Layjet technology was developed jointly with Vienna University of Technology and is also expected to reduce costs by 30 to 50%, depending on the composition of the ground.

The Layjet Micro-Rohr machine mills a slit trench ten centimeters beside the asphalt with a width of 15 to 18 centimeters and a depth of 35 to 70 centimeters. In the same operation, it lays the pipes and closes the trench again, using the removed and processed material. In a final step, following the laying process, the verge is made load-bearing again. Deutsche Telekom is currently testing the procedure, which has not yet been certified, in Schnaittach in Central Franconia, Bavaria, where 400 households are to be provided with FTTH (fiber to the home).