What is TIAEIA-568-B?
TIA/EIA-568-B is a set of three telecommunications standards from the Telecommunications Industry Association, a 1988 offshoot of the EIA. The standards address commercial building cabling for telecom products and services. The three standards are formally titled ANSI/TIA/EIA-568-B.1-2001, -B.2-2001, and -B.3-2001.
Top What do they mean by Balanced line? How does it work?
Balanced line operation is a transmission method which helps to eliminate the effects of noise on the cable. In the first diagram a coaxial cable is transmitting a 4V signal, this is unbalanced as all of the 4V signal is carried by the centre core of the coax with respect to the grounded screen. If 1V of noise is introduced, it adds to the signal being transmitted making 5V, this could interfere with our data.
With a balanced line transmission our 4V signal is split into +2V and -2V on one twisted pair, so we still have 4V between the two. Now when we introduce the 1V of noise, the +2V becomes +3V, and the -2V becomes -1V, but the potential difference between the two is still 4V. The devices we put on the ends of the cable to make the line balanced are called baluns, this name is derived from the function of the devices of converting between balanced and unbalanced transmission modes.
These days, more and more equipment is being designed to operate on balanced lines without the need for baluns, but there are still a lot of older systems out there that still use these converters.
Top What are ´The standards´?
There are three main cabling standards:
EIA/TIA 568A - This is the American standard and was the first to be published (1991).
ISO/IEC 11801 - The International standard for structured cabling systems.
CENELEC EN 50173 - The European cabling standard (the British version is BS EN 50173).
The reason for having a ´Standard´ is to define a method of connecting all types of vendors voice and data equipment, over a cabling system that uses a common media, common connectors and a common topology. This means that a building can be cabled for all its communications needs without the planner or architect ever having to know what type of equipment will be used.
Top What´s the pin assign of UTP cable ?
According to the EIA/TIA 586B standard, the color sequence of Cat.5 UTP is as following figure. The Straight-through cable is used to connect between switch and PC. The Cross-over cable is used to connect between two switches. If your switch provides uplink port, you could connect two switches through Straight-through cable by linking one side to uplink port.
Top What´s the pin assign of UTP cable ?
According to the EIA/TIA 586B standard, the color sequence of Cat.5 UTP is as following figure. The Straight-through cable is used to connect between switch and PC. The Cross-over cable is used to connect between two switches. If your switch provides uplink port, you could connect two switches through Straight-through cable by linking one side to uplink port.
Top What differences are between UTP, FTP, and STP cable?
UTP (Unshielded twisted-pair) cable relies solely on the cancellation effect produced by the twisted wire pairs to limit signal degradation caused by electromagnetic interference (EMI) and radio frequency interference (RFI). FTP (Foil screened twisted-pair) is also called ScTP (Screened twisted-pair). It is improved from UTP, combining the technique of shielding, but only wrapped in an overall metallic braid or foil.
Many cable installers and manufacturers may use the term STP to describe FTP cabling. Exactly, STP (Shielded twisted-pair) is different from FTP. STP cable combines the techniques of shielding, cancellation, and wire twisting. Each pair of wires is wrapped in a metallic foil. The four pairs of wires then are wrapped in an overall metallic braid or foil. As specified for use in Ethernet network installations, STP reduces electrical noise both within the cable (pair-to-pair coupling, or crosstalk) and from outside the cable (EMI and RFI). Although STP prevents interference better than UTP and FTP, it is more expensive and difficult to install. The metallic shielding must be grounded at both ends. If it is improperly grounded, the shield acts like an antenna and picks up unwanted signals. Because of its cost and difficulty with termination, STP is rarely used in Ethernet networks. STP is primarily used in Europe.
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