Bandwidth Capacity of Fiber Optic Cable

By Eric Novinson

Fiber optic cable
i optical fibre (fiber) 2 image by BlueMiniu from

Fiber optic cable transmits information using light signals. Fiber optic networks operate under the standards 10 Base-F, 100 Base-F, FDDI, FDDI duplex, 1000 Base-F and 10 Gbase, which include bandwidth capacity in their definitions.

Single and Multimode Fiber

Single mode fiber optic cable is the earliest form of fiber optic cable. This type of cable sends a single beam of light down the cable. Multimode fiber optic cable is an improved version of fiber optic communication. Because multimode fiber sends several light beams that combine into one signal, performance may be slightly higher, as the multimode installation includes several lasers which may combine to produce a maximum transmission rate greater than the specification standard rate to improve reliability. For example, a 10 gigabyte multimode network may include four lasers sending at 3 gigabytes.

10 Base-F

Older installations operate with lower bandwidth, especially if the signal is sent over long distances without amplification. The 10 Base-F standards from 1993 are the earliest standard for fiber optic transmission over Ethernet networks, according to the University of California, Berkeley. 10 Base networks send information at 10 megabytes per second.

Fiber Distributed Data Interface

FDDI, or fiber distributed data interface, is an alternative to an Ethernet network. FDDI is specifically designed for fiber optic communication, unlike Ethernet specifications designed for use with copper wires. FDDI uses both single mode cable to connect separate structures and multimode cable inside a structure, according to the University of California, Berkeley. FDDI networks are arranged in a ring of computers that pass an electronic token around the ring to communicate, this structure is known as a token ring network. The FDDI standard is a 100 megabyte per second network. FDDI-2 sends video images as well as data with a 100 megabyte per second standard. FDDI duplex mode sends data at double speed, allowing 200 megabyte per second communication.

Fast Ethernet

Some networks send data at 100 megabyte per second. The standards that govern these fiber networks are included in the 100 Base-F family. Any of the 100 Base, or 100 megabyte per second, standards including the fiber optic standard are referred to as Fast Ethernet.

1000 Base-F

Fiber Ethernet networks are installed under the 1000 Base-F standard. This standard allows transmission of data at one thousand megabytes per second. As with the other standard families there are related Ethernet specifications, such as 1000 Base-FX, that also operate at the same speed.

10 GBase

The 10 GBase standard covers Ethernet networks that include copper wires, wireless signals and fiber optic cables, so there is no separate 10 GBase-F standard. 10 Gbase standards govern networks that send information at 10 gigabytes per second.