100BaseVG

100BaseVG is a 100 Mbit/s Ethernet standard specified to run over four pairs of category 3 UTP wires (known as voice grade, hence the "VG"). It is also called 100VG-AnyLAN because it was defined to carry both Ethernet and token ring frame types.

100BaseVG was originally proposed by Hewlett-Packard, ratified by the ISO in 1995 and was practically extinct by 1998.

100BaseVG started in the IEEE 802.3 committee as Fast Ethernet. One faction wanted to keep CSMA/CD in order to keep it pure Ethernet, even though the collision domain problem limited the distances to one tenth that of 10BASE-T. Another faction wanted to change to a polling architecture from the hub (they called it "Demand Priority Protocol") in order to maintain the 10baseT distances, and also to make it a deterministic protocol. The first faction argued that, since IEEE 802.3 was the Ethernet committee, it was not the place to develop a different protocol. Thus, the IEEE 802.12 committee was formed and standardized 100BaseVG.

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