Multimode fiber has a larger core (typically 50 or 62. 5 microns) and can carry multiple light signals, usually LEDS, at once. While that's great for short distances, those overlapping signals can bump into each other and cause distortion over longer distances. Multimode fiber's bandwidth has to ability to cope along with higher data throughput over the shorter. Multi-mode optical fiber is a type of optical fiber mostly used for communication over short distances, such as within a building or on a campus. It is cost effective in equipment and installer friendly. While both cables use the same basic principles, each has its own advantages and disadvantages that make them ideally suited for a particular environment. Learning when it is appropriate to use each is critical. Single mode fiber has a very narrow core (around 8–10 microns in diameter), so it only allows one light signal (or "mode") to pass through at a time.