Definition of cabling in The Network Encyclopedia.
How Cabling Works
There are two basic types of cabling used in LAN networking environments:
- Copper cabling, which consists of insulated copper conductors that transmit signals using electrical voltages and currents. Copper cabling can be either coaxial cabling (such as thinnet or thicknet) that is used mainly in industrial environments, or the more commonly employed twisted-pair cabling. Twisted-pair cabling comes as either unshielded twisted-pair (UTP) cabling (commonly used in Ethernet or Fast Ethernet environments) or the less common shielded twisted-pair (STP) cabling (employed for token ring networks and sometimes for Gigabit Ethernet installations). Copper cabling is mainly used for shorter cable runs such as horizontal cable runs between wiring closets and wall plates in work areas, for patch cables, and for equipment interconnects.
- Fiber-optic cabling, which is made of glass strands that transmit signals as light waves or pulses. Fiber-optic cabling can be either single-mode, which is used for the longest cable runs, or multimode, which has a much higher carrying capacity. Fiber-optic cabling is generally used for backbone cable runs such as vertical rises in buildings and building-to-building interconnects on a campus, for high-speed interconnects between networking devices in a wiring closet, and for connections to high-speed servers and workstations.
The Telecommunications Industry Association (TIA) and Electronic Industries Alliance (EIA) have defined a series of standards on proper layout and organization of premise cabling called the EIA/TIA wiring standards. Cabling installed in a building must meet all legal requirements, including federal and local building regulations. Do not attempt to wire a building unless you are fully familiar with the required regulations. The EIA/TIA-568A Commercial Building Telecommunication Cabling Standard specifies standards for each of the following:
- Establishing wiring closets on each floor of the building to contain rack-mounted equipment such as hubs, switches, and patch panels
- Running vertical backbone plenum cabling through building risers and building plenums, for connecting wiring closets to the main equipment room
- Running horizontal PVC (polyvinyl chloride) cabling for each floor through false ceilings
- Connecting the patch panels in the wiring closet to wall plates in computer work areas
Specialized cables—such as serial, parallel, or SCSI cables—are used to connect peripherals, and therefore do not serve the same purpose as the cables just discussed. Serial cables and other special purpose cables are generally very short and are not permanently installed. Cabling for a LAN must be installed according to the standards described in the previous list. Not all networks use physical cabling. Wireless networks can use infrared, microwave, radio, or some other form of electromagnetic radiation to allow networking components to communicate with each other.
Choosing the right kind of cabling at the beginning of an installation can save considerable expense when networking equipment is later upgraded for higher transmission speeds.