Along with the standard information fiber optic cables (FOC), made with dielectric self supporting cables, overhead ground-wire cables made of steel wires with different coatings containing stainless steel module which comprises optical fibers in hydrophobic semi-liquid gel are widely used (OPGW). This design provides necessary mechanical strength and is a product of dual purpose: it performs the traditional role of protecting power lines from lightning strikes and used as communication and data transfer cable.
