10BASE5 (also known as thicknet) is the original "full spec" variant of
Ethernet cable, using special cable similar to RG-8/U
coaxial cable. This is a stiff, 0.375 inch (approx. 9.5 mm) diameter cable with an impedance of 50
ohms, a solid center conductor, a foam insulating filler, a shielding braid, and an outer jacket. The outer sheath is often yellow-to-orange/brown foam
fluorinated ethylene propylene (for fire resistance) so it frequently is just called "yellow cable", "orange hose", or sometimes humorously "frozen yellow garden hose". 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
broadband, and the 5 stands for the maximum segment length of 500
metres (approx 1600 feet).
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