Category 3 cable

was widely used in computer networking in the early 1990s for 10BASE-T Ethernet and, to a much lesser extent, for 100BaseVG Ethernet, Token Ring and 100BASE-T4. The original Power over Ethernet 802.3af specification supports the use of cable, but the later 802.3at Type 2 high-power variation does not. In some use cases and for short distances, may be capable of carrying 100BASE-TX (2 pairs) or even 1000BASE-T (4 pairs). Such use cases include hobbyist retrofitting short home telephone networks for Ethernet. Dedicated 100BASE-T4 networks, supporting over , appear to have been a rarity as very few network interface controllers and switches were ever released. Some examples include the 3com 3C250-T4 Superstack II HUB 100, IBM 8225 Fast Ethernet Stackable Hub and Intel LinkBuilder FMS 100 T4. The same applies to network interface controller cards. Bridging 100BASE-T4 with 100BASE-TX required additional network equipment. ==Replacement==

Starting in the mid-1990s, new structured cabling installations were often built with the higher performing cable required by 100BASE-TX. or is now used for all modern structured cabling installations. Many large institutions have policies that any upgrade to a network using must involve upgrading to . ==See also==