token ring

Attached Resource Computer Network, Fiber Distributed Data Interface (FDDI) and the token bus used the token ring. But the most broadly deployed token ring protocols were those of IBM, released in the mid-1980s, and the standardized version of it known as IEEE 802.5, which appeared in the late 1980s.

The use of token rings and 802.5 started declining in the 1990s. Today, they are considered inactive and obsolete. Enterprise organizations gradually phased out the token ring and adopted Ethernet technology, which dominates LAN designs today. The IEEE 802.5 working group is now listed as disbanded.

Token rings were popular because they worked well with large amounts of traffic, but they were not well suited to large networks, particularly if those networks were spread widely or had physically remote nodes. To overcome some of these limitations, multistation access units (MSAUs), which are like hubs on Ethernet, were added. MSAUs are centralized wiring hubs and are also known as concentrators.