This article will compare fiber optic and copper cables in terms of performance, durability, security, cost, and typical uses. Understanding these differences will help you pick the best option to meet your network's specific needs. Both technologies can deliver high-speed connectivity, but they behave differently under real-world constraints such as. Wavelength Division Multiplexing (WDM) technology expands fiber capacity by transmitting multiple signals at different wavelengths. A recent investor presentation by AT&T claimed that fiber was 35% less costly to maintain than copper. Copper networks use electrical signals through metal wires, while fiber networks send data as light pulses through.