Because of its high capacity and reliability, multi-mode optical fiber generally is used for backbone applications in buildings.

However, a multi-mode fiber introduces multimode distortion, which often limits the bandwidth and length of the link.

Instead, few-mode or multi-mode fibers need to be used.

It uses two strands of multi-mode optical fiber for receive and transmit.

It delivers serialized data at a line rate of 10.3125 Gbit/s over ten lanes of multi-mode fiber.

Such fiber is called multi-mode fiber, from the electromagnetic analysis (see below).

The electromagnetic analysis may also be required to understand behaviors such as speckle that occur when coherent light propagates in multi-mode fiber.

The term is also used, more loosely, in multi-mode optical fiber.

Single mode fibers are therefore better at retaining the fidelity of each light pulse over longer distances than multi-mode fibers.

For these reasons, single-mode fibers can have a higher bandwidth than multi-mode fibers.