Topic summary
CSMA/CD
Extracted from the Wikipedia article Carrier-sense multiple access with collision detection.
Applications
CSMA/CD was used in now-obsolete shared-medium Ethernet variants (10BASE5, 10BASE2), and in the early versions of twisted-pair Ethernet, which used repeater hubs. Modern Ethernet networks, built with switches and full-duplex connections, no longer need to use CSMA/CD, because each Ethernet segment, or collision domain, is now isolated. CSMA/CD is still supported for backwards compatibility and for half-duplex connections. The IEEE 802.3 standard, which defines all Ethernet variants, for historical reasons still bore the title "Carrier sense multiple access with collision detection (CSMA/CD) access method and physical layer specifications" until 802.3-2008, which uses new name "IEEE Standard for Ethernet".