10BASE5

10BASE5 (also known as thicknet) is the original "full spec" variant of Ethernet cable, using a stiff, large diameter coaxial cable with an impedance of 50 ohms and with multiple shielding. The outer sheath is often yellow polyvinyl chloride so it frequently is just called "yellow cable". The name 10BASE5 is derived from several characteristics of the physical medium. The 10 refers to its transmission speed of 10 Mbit/s. The BASE is short for baseband signalling as opposed to radio frequency, and the 5 stands for the maximum segment length of 500 metres.

10BASE5 cable is designed to allow transceivers to be added while existing connections are live. This is achieved using a vampire tap - a device which (with sufficient practise) clamps onto the cable, forcing a spike through the outer shielding to contact the inner conductor while other spikes bite into the outer conductor. This is often built into the transceiver and a more flexible multi-wire cable carries the connection between the transceiver and the node.

See also:

• 10BASE2
• 10BASE-T
• Computer network
• Ethernet

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Based on material from FOLDOC, used with permission.