1Base5

The IEEE standard (mid-1980s) for Ethernet transmission over Cat 3, Cat 4, or Cat 5 unshielded twisted pair (UTP) cable. 1Base5 translates to 1 Mbps (theoretical transmission rate), Baseband (one transmission at a time over a single, shared channel), and 500 meters maximum segment length.The predecessor to 10Base-T, 1Base5 is considered obsolete. See also 10Base-T, baseband, Cat 3, Cat 4, Cat 5, channel, Ethernet, IEEE, and transmission rate.