In 10BASE-X, the 10 represents its maximum throughput of 10 Mbit/s, BASE indicates its use of baseband transmission, and X indicates the type of medium used.
In 10BASE-F, the 10 represents a maximum throughput of 10 Mbit/s, BASE indicates its use of baseband transmission, and F indicates that it relies on a medium of fiber-optic cable.
It was specially designed as a back-to-back transport between repeater hubs to decrease latency and collision detection time, thus increasing the possible network radius.
It replaces the original fiber-optic inter-repeater link (FOIRL) specification, but retains compatibility with FOIRL-based equipment.
Due to the synchronous operation of 10BASE-FB, delays normally associated with Ethernet repeaters are reduced, thus allowing segment distances to be extended without compromising the collision detection mechanism.
This variant calls for a non-powered optical signal coupler capable of linking up to 33 devices, with each segment being up to 500 m in length.