Glossary

A balanced four-pair UTP with a single foil or braided screen surrounding all four pairs in order to minimize EMI radiation or susceptibility. Screened twisted-pair is also sometimes called foil twisted-pair (FTP). ScTP is a shielded version of Category 3, 5, 5e, and 6 UTP cables; they are less susceptible to EMI than UTP cables but are more susceptible than STP cables.

Also known as PABX Secondary.
Secondary adaptor - Used where a second phone is sharing the same telephone office exchange, PABX extension number.

A portion of a network that uses the same length of cable (electrically contiguous). Also the portion of a network that shares a common hub or set of interconnected hubs.

A trade name used by the Nippon Sheet Glass Company for a graded-index fiber lens. A segment of graded index fiber made to serve as a lens.

In wire industry terminology, a material possessing electrical conductivity that falls somewhere between that of conductors and insulators. Usually made by adding carbon particles to an insulator. This is not necessarily the same as semiconductor materials such as silicon or germanium.

A laser in which the injection of current into a semiconductor diode produces light by recombination of holes and electrons at the junction between p- and n-doped regions. Also called a semiconductor diode laser.

For a fiber-optic receiver, the minimum optical power required to achieve a specified level of performance, such as BER.

Pertaining to wire and cable, a layer of insulating material such as textile, paper, or Mylar, which is placed between a conductor and its dielectric, between a cable jacket and the components it covers, or between various components of a multiple conductor cable. It can be utilized to improve stripping qualities or flexibility, or it can offer additional mechanical or electrical protection to the components it separates.

Markings on the outside of a fiber-optic cable to aid in measuring the length of the cable.

See daisy chain.

A loop or slack left in a cable when the cable is installed and terminated. This loop allows future trimming of the cable or movement of equipment if necessary.

A type of optical fiber connector that is designed to take up less physical space than a standard-sized connector. An SFF connector provides support for two strands of optical fiber in a connector enclosure that is similar to an RJ-45. There is currently no standard for SFF connectors; types include the LC and the MT-RJ connectors.

Foil and braid screened (SHIELDED) twisted pair

An outer protective layer of a fiber-optic or copper cable that includes the cable jacket, strength members, and shielding.

A metallic foil or multiwire screen mesh that is used to reduce electromagnetic fields from penetrating or exiting a transmission cable. Also referred to as a screen.