The world?s largest network has been developed via a PhD thesis by a student at the Public University of Navarre in Spain. Montserrat Fernandez-Vallejo used her telecommunications engineering knowledge to come up with a 250 km (155 miles) fiber optic network.

Her creation allows two or more information channels to be combined within a single transmission medium. Its multiplexing capability is positioned to remotely monitor large infrastructures.
Fernandez gave the example of analysis of marine platforms monitored from a central hub even hundreds of kilometers away. Sensors would send information back regarding critical states to
enable correcting maintenance to be undertaken. In fiber optics, the data carried by light would travel along a very thin strand of glass or
plastic.

Fernandez points out the benefits: "With multiplexing, firstly, we share the same transmission medium to broadcast information coming from different sources, and secondly, we share the transmitter and the receiver.?

Fiber-optic sensor networks are used where the structure is very expensive, such as oil pipelines, high voltage lines, or in locations with possible risk to human life, such as nuclear plants, chemical product warehouses, bridges, and dams, or when a perimeter requires monitoring.