Structured Cabling

Buildings today should be wired in accordance with guidelines known as “Structured Cabling“. The basic objective of this system is to minimize future costs for moves and additions, and to maximize availability, reliability, and configurability. The method by which this reliability and cost saving is accomplished by pulling only one type of wire which can be used for any variety of network….telephone, serial terminals, and printers. All configuration of the wiring system is done at a single point, a” wiring closet” on each floor to which every cable on that floor runs. Floor wiring closets are connected by a riser cable.

Each workstation should have a minimum of two 4 pair Cat 5 cables: one for network and the other for telephone. These cables run from a wall jack at the workstation to a patch panel or backboard termination device (110 frame and blocks) in the wiring closet.

Four pair cable is practically universal. Even if your network uses only 2 pairs, and the cable contains 4 pairs, it is considered very bad form to run two network connections through that one cable. One reason is the possibility of interference between the two connections slowing down your network and another is that should you upgrade to a faster network that uses all 4 pairs. A third reason is that it can make things messy and difficult to interpret at the backboard or patch panel. Telephone lines can share the same cable without serious problems, except for upgrade and interpretability considerations.

In the wiring closet on each floor will be a “hub” to which each workstation network cable leads. Sometimes there is a server on each floor as well, which may or may not be in the wiring closet. Hubs, repeaters, and other distribution devices are connected to each other through a “backbone cable” which may be Cat 5e, Cat 6, coax, or fiber optic depending on the unique needs of your installation.

The maximum run for any workstation to an active device (hub, repeater, etc…) is 100 meters (actual cable length).

August 9, 2011
Comments Off on Structured Cabling