Token Ring
termnetworking
The deterministic LAN technology (IEEE 802.5) where a circulating token grants the right to transmit, championed by IBM against Ethernet.
Stations on a logical ring pass a token; only the holder transmits, so there are no collisions and latency is predictable under load, which is exactly what Ethernet of the era could not promise. Running at 4 and 16 Mbit/s with a 100 Mbit/s high-speed successor, it owned IBM-centric enterprises through the mid-1990s before switched Ethernet's economics ended the war. Technically elegant and commercially defeated, it remains networking's great counterfactual.
Also known as: IEEE 802.5