Specifications - Definitions
1. Application (in terms of cabling infrastructure): The application layer is the OSI layer closest to the end user, which means both the OSI application layer and the user interact directly with the software application. When determining resource availability, the application layer must decide whether sufficient network or the requested communication exists.. (OSI_model#Layer_7:_application_layer)
2. Unshielded twisted-pair: UTP cable is a popular cable used in computer networking that consists of two shielded wires twisted around each other. In the image to the right, is an example of the different network cables you're likely to encounter. (/jargon/u/utpcable.htm)
3. Shielded Twisted-pair: Twisted Pair (STP) has a fine wire mesh surrounding the wires to protect the transmission; Unshielded Twisted Pair (UTP) does not. Shielded cable is used in older telephone networks, network, and data communications to reduce outside interference. In the picture to the right, is an example of what these cables look like inside. (jargon/t/twispair.htm)
4. Fiber-Optic cable: A fiber optic cable is a network cable that contains strands of glass fibers inside an insulated casing. These cables are designed for long distance and very high bandwidth (gigabit speed) network communications. (Mitchell)
5. Dark Fiber: Dark fiber refers to unused fiber-optic cable. Often times companies lay more lines than what's needed in order to curb costs of having to do it again and again. The dark strands can be leased to individuals or other companies who want to establish optical connections among their own locations. (TERM/D/dark_fiber.html)
6. Coaxial Cable: is a type of cable for high bandwidth data transmission use that typically consists of a single copper wire that is surrounded by a layer of insulation and then by a grounded shield of braided wire or an extruded metal tube. The whole thing is usually wrapped in another layer of insulation and, finally, in an outer protective layer. (/coaxial_cable.html)
7. Plenum: In building construction, a plenum (pronounced PLEH-nuhm, from Latin meaning full) is a separate space provided for air circulation for heating, ventilation, and air-conditioning (sometimes referred to as HVAC) and typically provided in the space between the structural ceiling and a drop-down ceiling. A plenum may also be under a raised floor. In buildings with computer installations, the plenum space is often used to house connecting communication cables. Because ordinary cable introduces a toxic hazard in the event of fire, special plenum cabling is required in plenum areas. (Lomas, 2005)
8. Riser: suitable for use inside walls and in open areas but not in places where air circulates, such as above suspended ceilings. Riser-rated cable is fire-resistant but can give off noxious fumes when overheated (/glossaries/riser-rated/4956753-1.html)
9. Rip Cord: Of an optical cable, a parallel cord of strong yarn that is situated under the jacket(s) of the Cable for the purpose of facilitating Jacket removal preparatory to Splicing or breaking out. (Rip-Cord.html)
10. Core: the conducting wire with its insulation in an electric cable (dictionary/core)
11. Attenuation: Attenuation is a telecommunications term that refers to a reduction in signal strength commonly occurring while transmitting analog or digital signals over long distances. (Janssen)
12. Noise: is any disturbance that interferes with data transmission and corrupts the quality of the signal. Below are some examples of where noise can be encountered in data transmission and common causes. (/jargon/n/noise.htm)
13. Headroom: also called Attenuation-to-crosstalk ratio (ACR), is the difference, expressed as a figure in decibels (dB), between the signal attenuation produced by a wire or cable transmission medium and the near-end crosstalk (NEXT). (Rouse, 2006)
14. ANSI: ANSI, which stands for the “American National Standards Institute”, has served