Category 6 and 6a Cables

The next level in the cabling hierarchy is Category 6 (CAT6) (ANSI/TIA/EIA-568-B.2-1), which was ratified by the TIA/EIA in June 2002. CAT6 provides higher performance than CAT5e and features more stringent specifications for crosstalk and system noise.

The quality of the data transmission depends upon the performance of all the components of the channel. So to transmit according to CAT6 specs, the jacks, patch cables, patch panels, cross-connects, and cabling must all meet CAT6 standards. (The channel includes everything from the wallplate to the wiring closet.) The CAT6 components are tested individually, and they are also tested together for performance. In addition, the standard calls for generic system performance so that CAT6 components from any vendor can be used in the channel.

CAT6 channel transmission requirements should result in a Power-Sum Attenuation-to-Crosstalk Ratio (PS-ACR) that’s greater than or equal to zero at 200 MHz.

In addition, all CAT6 components must be backward compatible with CAT5e, CAT5, and CAT3. If different category components are used with CAT6 components, then the channel will achieve the transmission performance of the lower category. For instance, if CAT6 cable is used with CAT5e jacks, the channel will perform at a CAT5e level.

CAT6a is a 10-Gigabit Ethernet (10-GbE) over copper standard. Its requirements are covered in ANSI/TIA-568-C.2 (Balanced Twisted-Pair Telecommunications Cabling and Components Standard) published in August 2009. The standard defines 10-Gigabit data transmission over a 4-connector twisted-pair copper cable for a distance of 100 meters on CAT6a copper cabling. This ensures that the system is ready to support IEEE 802.3an, the IEEE standard for 10GBASE-T, which specifies using Class E-augmented cable.

CAT6a extends electrical specifications from 250 MHz to 500 MHz. It also features Power-Sum Alien Crosstalk (PS-ANEXT) to 500 MHz. Alien Crosstalk (ANEXT) is a coupled signal in a disturbed pair arising from a signal in a neighboring cable.

To virtually eliminate the problem of ANEXT, CAT6a F/UTP cable is used. The F indicates an outer foil shield that eliminates PS-ANEXT. When security is an issue, CAT6a is a good choice because it doesn’t emit signals. In addition, CAT6a F/UTP cable works well in noisy environments with a lot of EMI.

More about Alien Crosstalk or 10-Gigabit Ethernet

Learn more:
Category 7/Class F