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Two types of cables are recognized and recommended for use in the horizontal cabling system. These cables are: 1. four-pair 100 Ohm unshielded twisted-pair (UTP) or screened twisted-pair (ScTP) cables, 0.51 mm (24 AWG) to 0.64 mm (22 AWG) in diameter. NOTE: Performance requirements for cables specified in ANSI/TIA/EIA-568-B.2. The recognized categories of UTP cabling are: · Category 5e: This designation applies to 100 Ohm UTP cables and associated connecting hardware whose transmission characteristics are specified up to 100 MHz. . | UPCOMING CHANGES IN CABLING STANDARDS The networking industry changes very rapidly. One contributing factor to the explosive growth of LANs WANs and the Internet has been the ANSI TIA EIA-568-A cabling standards in place since 1995. Standards greatly facilitate network interoperability network design network device and component manufacture and network installation. Throughout this curriculum you will see references to the ANSI TIA EIA-568-A standards. Replacement standards known the ANSI TIA EIA-B.1 B.2 and B.3 standards are scheduled to be completed and released in 2001. But until all of the ANSI TIA EIA-568-B standards are released the A standards remain in effect. Among other improvements these standards will be in much better alignment with the standards used outside the US - especially the ISO IEC 11801 updated standards. The ANSI TIA EIA-B.1 standards not yet released will deal with General Requirements Cabling and Field Testing. They are particularly important for network design of copper and fiber systems. The ANSI TIA EIA-B.2 standards also not yet released will deal with Copper Requirements Cabling and Connectors. These standards will be very specific. The ANSI TIA EIA-B.3 standards released in April of 2000 deal with Fiber Requirements Connectors and Cables. In general these new standards enable the installation of higher bandwidth copper technologies such as 100BASE-TX and 1000BASE-T and higher bandwidth optical fiber systems such as 1000BASE-LX and 1000BASE-SX . A notable specific change for copper is that Category 5e e for enhanced is now the minimum specified data cable. Cat 5e differs from Cat 5 in that it is required to pass more complex tests in order to guarantee its reliability for high bandwidth communications. A notable specific change for optical fiber is the recognition of small form-factor SFF connectors. This document provides a detailed summary of the upcoming cabling standards developments. It is a combination of the aNsI TIA .
