Structured cabling (a.k.a. premises distribution system) is a type of communication cabling system. This is a generic communication wiring scheme that is installed in buildings. It can support all different kinds of communication systems. These include telephone systems, computer LANs, video systems and imaging systems.
The Purpose Of A Structured Cabling System
Standardized cabling systems are meant to support a multi-product and multi-vendor environment. However, it will cost you less to install and maintain this type of a system over its lifespan than it would cost you to install and maintain any other type of system. This system includes communication cabling, cable pathways, communication ground and bonding system, supporting structures and building spaces.
Structured Cabling Standards
There are three main cabling standards:
- EIA/TIA 568C is the American standard
- ISO/IEC 11801 is the International standard
- CENELEC EN 50173 is the European standard
Structured Cabling Subsystems
The structured cabling system is based upon modular subsystems. These subsystems are independent but they do work together in order to create a complete building cabling system. Each subsystem is independently designed and installed from the other subsystems. However, all of the structured cabling systems are interconnected and thus they do work together as one single cabling system. Thanks to this concept both growth and flexibility are possible within one subsystem and this will not affect the other systems. In order to better understand how each of these subsystems work, you must take a look at them individually.
The Work Area Subsystem
The work area subsystem is where the horizontal cable terminates at the wall outlet. Herein the users and the telecommunications equipment connect to the structured cabling infrastructure. The following components are included within the work area subsystem:
- Cabling (Cat5e, Cat 6 copper patch cables, jumpers, modular cords and adapters)
- Adapters (i.e. baluns) that modify the cable’s signal or impedance
- Station equipment (i.e. computers, telephones, fax machines, data terminals)
The Horizontal Subsystem
Horizontal cabling extends from telecommunication closets to the work area. It terminates within telecommunication outlets. The following components are included within the horizontal subsystem:
- Cables from the patch panel to the work area
- Telecommunication outlets
- Cable terminations
- Cross connections
The Backbone Subsystem
The backbone system is used to connect entrance facilities, equipment rooms and telecommunication closets. It consists of cables that connect the telecommunication closets, equipment rooms and building entrance with the cross-connect cables, mechanical terminations and patch cables that are used for backbone-to-backbone cross-connection. The following components are utilized within this subsystem:
- Cabling between equipment rooms and building-entrance facilities
- Cabling between the buildings’ entrance facilities
- Vertical connections between floors
The Telecommunication Room (a.k.a. TR)
This is the space within a building that is used to terminate horizontal and backbone cables. Its primary function is to have a dedicated space where you can install cable termination hardware and communications equipment. Herein you will also find networking equipment (i.e. LAN hubs, switches, routers, repeaters). These rooms are where the backbone cabling equipment rooms terminate.
The Equipment Room (a.k.a. ER)
This is a special kind of telecommunications equipment room that is found within a centralized space. Herein the more sophisticated communications or data equipment is housed within a controlled environment. Oftentimes, telephone equipment or data-networking equipment (i.e. routers, switches, hubs) is located here too. Backbone cabling is set up so that it will terminate within the equipment room too.
The Entrance Facility (a.k.a. EF)
The entrance facility is usually where the service providers (i.e. the telephone company) bring their cables into a building. It is these cables that will then provide the services (i.e. dial tone) that the building needs in the way of phone services.