Category 6 cable
Cat 6- Category - 6, (ANSI/TIA/EIA-568-B.2-1) is a cable standard for Gigabit Ethernet and other network protocols that is backward compatible with the Category 5/5e and Category 3 cable standards. Cat-6 features more stringent specifications for crosstalk and system noise. The cable standard provides performance of up to 250 MHz and is suitable for 10BASE-T / 100BASE-TX and 1000BASE-T (Gigabit Ethernet). It is expected to suit the 10GBASE-T (10Gigabit Ethernet) standard, although with limitations on length if unshielded Cat 6 cable is used.
The cable contains four twisted copper wire pairs, just like earlier copper cable standards. Although Cat-6 is sometimes made with 23 gauge wire, this is not a requirement; the ANSI/TIA-568-B.2-1 specification states the cable may be made with 22 to 24 AWG gauge wire, so long as the cable meets the specified testing standards. When used as a patch cable, Cat-6 is normally terminated in 8P8C modular connectors, often incorrectly referred to as "RJ-45" electrical connectors. Some Cat-6 cables are too large and may be difficult to attach to 8P8C connectors without a special modular piece and are technically not standard compliant. If components of the various cable standards are intermixed, the performance of the signal path will be limited to that of the lowest category. As with all cables defined by TIA/EIA-568-B, the maximum allowed length of a Cat-6 horizontal cable is 90 meters (295 feet). A complete channel (horizontal cable plus cords on either end) is allowed to be up to 100 meters in length, depending upon the ratio of cord length:horizontal cable length.
The cable is terminated in either the T568A scheme or the T568B scheme. It doesn't make any difference which is used, as they are both straight through (pin 1 to 1, pin 2 to 2, etc). Mixing T568A-terminated patch cords with T568B-terminated horizontal cables (or the reverse) does not produce pinout problems in a facility. Although it may very slightly degrade signal quality, this effect is marginal and certainly no greater than that produced by mixing cable brands in-channel. To connect two Ethernet units of the same type and function in a peer-to-peer connection (Personal Computer to Personal Computer, or hub to hub, for example) a cross over cable should be used, though some modern hardware can utilize either type of cable automatically.
The T568B Scheme is by far the most widely used patch cable (straight through) method of terminating the cables. For crossover cables, one end should be wired using the T568A scheme and the other end should be wired using the T568B scheme. This will ensure that the Transmit (TX) pins on both ends are wired through to the Receive (RX) pins on the other end. Crossover is used for hub to hub, computer to computer, wherever two-way communication is necessary. (not needed for client-server communication)
Pin | Pair | Wire | Color |
---|---|---|---|
1 | 3 | 1 | |
2 | 3 | 2 | |
3 | 2 | 1 | |
4 | 1 | 2 | |
5 | 1 | 1 | |
6 | 2 | 2 | |
7 | 4 | 1 | |
8 | 4 | 2 |
Pin | Pair | Wire | Color |
---|---|---|---|
1 | 2 | 1 | |
2 | 2 | 2 | |
3 | 3 | 1 | |
4 | 1 | 2 | |
5 | 1 | 1 | |
6 | 3 | 2 | |
7 | 4 | 1 | |
8 | 4 | 2 |
Augmented Category 6 (Category 6a)
The TIA is working to complete a new specification that will define enhanced performance standards for unshielded twisted pair cable systems. Draft specification ANSI/TIA/EIA-568-B.2-10 specifies cable systems, called "Augmented Category 6" or more frequently as "Category 6a", that operate at frequencies up to 500 MHz and will provide up to 10 Gbit/s bandwidth. The new specification has limits on alien crosstalk in cabling systems.
Augmented Category 6 specifies cable operating at minimum frequency of 500 MHz, for both shielded and unshielded. It can support future 10 Gbit/s applications up to the maximum distance of 100 meters on a 4-connector channel.