Ethernet over fiber

Ethernet over fiber is a networking technology that delivers Ethernet bandwidth ranging up to 400 Gbit/s using optical fiber lines. Such wired transmission methods extend connectivity over long distances up to 200 km, support higher bitrates and provide far greater immunity from electromagnetic interference (EMI) than electrical connections. Copper-based Ethernet connections are generally limited to a maximum length of 100 meters or less, a maximum speed of 40 Gbit/s, and they are more easily affected by surrounding EMI.

Background
Ethernet over fiber has emerged as a preferred medium in situations that require long-distance communication, high speeds or a high level of immunity from electromagnetic interference (EMI). With fiber-optic cables, data can be transmitted over much greater distances compared to copper-based Ethernet cable.

Ethernet over fiber-optic cable has been a technology with specifications dating back to the mid 1980s (10BASE-F). Initially, fiber-optic cables were primarily used to connect repeaters when the distance between them exceeded the limitations of ThickNet cable. The initial specification, known as Fiber Optic Inter Repeater Link (FOIRL), outlined the process of linking two repeaters using fiber-optic cable, allowing for connections of up to 1,000 meters (3,280 feet) in length. With the disappearance of half-duplex connections and improvements in fiber-optic communication, distances and data rates increased greatly.