Glossary

The light-gathering ability of a fiber, defining the maximum angle to the fiber axis at which light will be accepted and propagated through the fiber. The numerical aperture is determined by the refractive indexes of the core and cladding. The numerical aperture is also used to determine the fiber

The part of the infrared spectrum near the visible spectrum, typically 700nm to 1500nm or 2000nm; it is not rigidly defined.

Defined in copper twisted pair cables as the end of the cable where the transmitter is located.

The distribution of the irradiance over an emitting surface (over the cross section of an optical waveguide).

The U.S. electrical wiring code that specifies safety standards for copper and fiber-optic cable used inside buildings. See Chapter 4 for more information.

The optical input power to a detector needed to generate an electrical signal equal to the inherent electrical noise.

Ties things together. Computer networks connect all types of computers and computer-related peripherals

The physical cables that link computers in a network; also known as physical media.

Crosstalk noise between two twisted pairs measured at the near end of the cable. Near is defined as the end of the cable where the transmission originated. 

The fire test method that measures flame spread, peak smoke optical density, and average smoke optical density. Formerly referred to as UL 910. Cables are required to pass this test and be listed by a nationally recognized test laboratory (e.g., UL or ETL) for the cables to be allowed to be placed in plenum spaces.

A circuit board installed in a computing device that is used to attach the device to a network. A NIC performs the hardware functions that are required to provide a computing device physical communications capabilities with a network.

Software utilities that verify that the NIC is functioning correctly and that test every aspect of NIC operation, including connectivity to other nodes on the network.

Endpoint of a network connection. Nodes include any device connected to a network such as file servers, printers, or workstations.

Industry name for the 3G radio equipment at a RAN site

Initial jumper connecting onto an BTS/NodeB towards the main feeder cable, diplexor, MRC, UCU etc