I N D I A P R I V A T E L I M I T E D
Most important design considerations include :
- Life cycle
- MACs (Moves, adds, and changes)
Other important design considerations :
- Future Technology
- Location of users
- Power over Ethernet
- Wireless access points
a) Horizontal cabling
The horizontal cabling system encompasses everything between the telecommunications room cross-connects to the telecommunications outlets in the work area. It’s called horizontal because the cable typically runs horizontally above the ceiling or below the floor from the telecommunications room, which is usually on the same floor.
b) Backbone cabling
The backbone system encompasses all the cabling between telecommunications rooms, equipment rooms, entrance facilities, and between buildings.
c) Telecommunications room
The telecommunications room holds the termination equipment needed to connect the horizontal wiring to the backbone wiring. A building must contain at least one telecommunications room, and it should be on the floor it serves.
d) Work area
The work area consists of all the components between the telecommunications outlet and the user’s workstation equipment.
e) Equipment room
Following standard practices ensures current and future occupants of a building have all the information they need for smooth operations. Administrative record keeping is detailed in TIA/EIA-606-A:Administration Standard for Commercial Telecommunications Infrastructure. It specifies identification, labeling, and documentation for different components of the structured cabling system, including :
- Telecommunications pathways (horizontal and backbone)
- Telecommunications spaces (telecommunications rooms, work areas, equipment rooms, etc.)
- Connecting hardware and splices
- Grounding and bonding
Category 3 (CAT3) cable is rated for networks operating up to 16 Mbps. It is suitable for voice transmissions (not VoIP).
Category 4 cable is rated for transmission of 16 Mbps up to 100 meters. It is considered obsolete.
Category 5 (CAT5) cable was common for 100-Mbps LANs. It was ratified in 1991 and is now considered obsolete.
Enhanced Category 5 (CAT5e /Class D) cable, ratified in 1999, was designed to enable twisted-pair cabling to support full-duplex, 100-MHz applications such as 100BASE-TX and 1000BASE-T. CAT5e introduces stricter performance parameters such as Power-Sum Near-End Crosstalk (PS-NEXT), Equal-Level Far-End Crosstalk (EL-FEXT), and Power-Sum Equal-Level Far-End Crosstalk (PS-ELFEXT). It also introduces channel and component testing.
Category 6 (CAT6 /Class E) cable easily handles Gigabit Ethernet (1000BASE-T) applications. It’s a 100-ohm cable with a frequency of 250 MHz. CAT6 has far more stringent performance parameters than CAT5e, and is characterized by channel, link, and component testing. In addition, CAT6 components must be backwards compatible with lower-level components.
Augmented Category 6 (CAT6a /Class EA) is a relatively new standard, is designed to meet or exceed the requirements of 10-Gigabit Ethernet over copper at 100 meters. It extends the frequency range of CAT6 from 250 MHz to 500 MHz. Like CAT6, it includes an integrated set of channel, permanent link, and component requirements. It introduces an Alien Crosstalk (ANEXT) measurement for closely bundled “six around one” cable configurations. Both UTP and F/UTP cables can be used in CAT6a deployments. The F/UTP cable, though, virtually eliminates the problem of ANEXT. CAT6a cabling is the system of choice for new installations.
Category 7 /Class F is only an ISO/IEC 11801:2002 standard. It’s designed to meet or exceed the requirements of 10-Gigabit Ethernet. The standard specifies a frequency of 1–600 MHz over 100 meters of fully shielded twisted-pair cabling. Category 7 cable consists of four individually shielded pairs inside an overall shield. It’s called Shielded / Foiled Twisted Pair (S/FTP) or Foiled / Foiled Twisted Pair (F/FTP). With both, each twisted pair is enclosed in foil. In S/FTP cable, the four pairs are encased in an overall metal braid. In F/FTP, the four pairs are encased in an overall foil shield. The fully shielded cable virtually eliminates crosstalk between the pairs. In addition, the cables are noise resistant, making the Category 7 system ideal for high EMI areas. It’s well suited for applications where fiber optic cable would typically be used but costs less.
Category 7a / Class FA is a pending ISO class based on the use of S/FTP cable to 1000 MHz. 10-GbE and twisted-pair cable.
Optical Fiber cable technology uses light as an information carrier. The cable consists of a core, a single continuous strand of glass or plastic that’s measured in microns (μ) by the size of its outer diameter. This is the pathway for light rays carrying data signals. Fiber is the preferred cable for applications that require high bandwidth, long distances, and immunity to electrical interference. It’s the most commonly installed backbone cable as well. The advantages of fiber includes :
- Greater bandwidth
- Low attenuation and greater distance
A structured cabling system is the wiring network that carries all your data, voice, multimedia, security, VoIP, PoE, and even wireless connections throughout your building or campus. It includes everything from the data center to the desktop, including cabling, connecting hardware, equipment, telecommunications rooms, cable pathways, work areas, and even the jacks on the wallplate in your office. Today’s networks are complex systems running on technologies that no one could have imagined a few years ago.
A structured cabling system that’s smartly designed takes careful planning. Systems are more complex now than ever, and will get even more so as speed and bandwidth demands increase. The system you plan today will be supporting new and different applications for many years.