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Cat5/Cat6 DistributionCat-5 is based on the EIA/TIA 568 Commercial Building Telecommunications Wiring Standard developed by the Electronics Industries Association as requested by the Computer Communications Industry Association in 1985.
Category 5 cable , commonly known as Cat 5 , is an unshielded twisted pair type cable designed for high signal integrity. The actual standard defines specific electrical properties of the wire, but it is most commonly known as being rated for its Ethernet capability of 100 Mbit/s. Its specific standard designation is EIA / TIA-568 . Cat 5 cable typically has three twists per inch of each twisted pair of 24 gauge copper wires within the cable. The twisting of the cable reduces electrical interference and crosstalk . Another important characteristic is that the wires are insulated with a plastic ( FEP ) that has low dispersion , that is, the dielectric constant of the plastic does not depend greatly on frequency . Special attention also has to be paid to minimizing impedance mismatches at connection points.
Catergory 6
Trends of the past and the predictions for the future indicate that data rates have been doubling every 18 months. Current applications running at 1 Gb/s are really pushing the limits of Category 5e cabling. As streaming media applications such as video and multi-media become commonplace, the demands for faster data rates will increase and spawn new applications that will benefit from the higher bandwidth offered by Category 6. This is exactly what happened in the early '90s when the higher bandwidth of Category 5 cabling compared to Category 3 caused most local area network (LAN) applications to choose the better media to allow simpler, cost effective, higher speed LAN applications, such as 100BASE-TX. It is also important to note that cabling infrastructure is generally considered a 10 year investment as opposed to two of three years for electronics. Work has already started on 10G. BASE-T, and Category 5e cabling is not being considered. With additional throughput requirements right around the corner, it makes sense to plan ahead.
Note: Bandwidth is defined as the highest frequency up to which positive power sum ACR (attenuation-to-crosstalk ratio) is greater than zero.
What is the general difference between Category 5e and Category 6?
The general difference between Category 5e and Category 6 is in the transmission performance and extension of the available bandwidth from 100 MHz for Category 5e to 200 MHz for Category 6. This includes better insertion loss, near end crosstalk (NEXT), return loss and equal level far end crosstalk (ELFEXT). These improvements provide a higher signal-to-noise ratio, allowing higher reliability for current applications and higher data rates for future applications. The additional performance parameters provide a sort of "forgiveness factor" for things that happen within a cabling infrastructure over its lifetime assuring that bandwidth remains available for applications.
Please note that the bandwidth referred to above is the bandwidth to achieve a positive signal to noise ratio between insertion loss and power sum near end crosstalk (PSACR is greater than 0). Cat 6 cabling performance is specified to 250 MHz, or 25 percent beyond the 0 dB PSACR frequency of 200 MHz.
Will Category 6 supersede Category 5e?
Yes, analyst predictions and independent polls indicate that 80 to 90 percent of all new installations will be cabled with Category 6. The fact that Category 6 link and channel requirements are backward compatible to Category 5e makes it very easy for customers to choose Category 6 and supersede Category 5e in their networks. Applications that worked over Category 5e will work over Category 6. |
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