Single-mode optical fibre
In fibre optic communication, a single-mode optical fibre is an optical fibre designed to carry only a single ray of light (mode). This ray of light often contains a variety of different wavelengths. Although the ray travels parallel to the length of the fibre, it is often called the transverse mode since its electromagnetic vibrations occur perpendicular (transverse) to the length of the fibre. Data rates are limited by polarisation mode dispersion and chromatic dispersion. In 2005, data rates of up to 10 gigabits per second were possible at distances of over 60 km with commercially available transceivers (Xenpak). By using optical amplifiers and dispersion-compensating devices, state-of-the-art DWDM optical systems can span thousands of kilometers at 10 Gbit/s, and several hundred kilometers at 40 Gbit/s.
Multi-mode optical fibre
Multi-mode optical fibre (multimode fibre or MM fibre or fibre) is a type of optical fibre mostly used for communication over shorter distances, such as within a building or on a campus. Typical multimode links have data rates of 10 Mbit/s to 10 Gbit/s over link lengths of up to 600 metres – more than sufficient for the majority of premises applications. The equipment used for communications over multi-mode optical fibre is much less expensive than that for single-mode optical fibre.