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Home , Category 3 cable, Category 5 cable, Category 6 cable

SIIS Level 3 – Cable Specifications

Spec Cable Cable Application Notes Length Gauge Range CAT 5 ANSI/TIA/EIA-568-A 328ft (100m) 24 AWG 100Base-TX 1-100MHz UTP UTP. NEXT performance slightly better than TIA/EIA-568-B 328ft (100m) 24 AWG 1000Base-T 1-100MHz CAT 5e CAT5 UTP. Better insertion loss, near end (NEXT), return loss, higher SNR ANSI/TIA-568-B.2-1 328ft (100m) 22-24 AWG 1000Base-T 1-250MHz CAT 6 (usually 23 AWG) and equal level far end crosstalk (ELFEXT) than CAT5e. ANSI/TIA/EIA-568-B.2-10 328ft (100m) 22-24 AWG 1000Base-T 1-500Mhz UTP CAT 6a (usually 23 AWG) ISO/IEC 11801:2002 cat 7 328ft (100m) 22-24 AWG 10000Base-T 1-600MHz STP CAT 7 class F (usually 23 AWG)

UTP (Unshielded ) is twisted pair cabling that contains no shielding STP (Shielded Twisted Pair cable) has each individual pair shielded, plus an overall screen around the four individually shielded pairs. ScTP (Screened Twisted Pair) is 4-pair 100 UTP, with a single foil or braided screen surrounding all four pairs

UTP STP ScTP

2/13/2008 SIIS – Level 3 Gregor Deans

Category 5 - The original specification for was defined in ANSI/TIA/EIA-568-A, with clarification in TSB-95. These documents specified performance characteristics and test requirements for of up to 100 MHz.

Category 5 cable includes four twisted pairs in a single cable jacket. This use of balanced lines helps preserve a high signal-to-noise ratio despite interference from both external sources and other pairs (this latter form of interference is called crosstalk). It is most commonly used for 100 Mbit/s networks, such as 100BASE-TX , although IEEE 802.3ab defines standards for 1000BASE-T - over category 5 cable. Cat 5 cable typically has three twists per inch of each twisted pair of 24 gauge copper wires within the cable.

Category 5e - an enhanced version of Cat 5 that adds specifications for far end crosstalk. It was formally defined in 2001 in the TIA/EIA- 568-B standard, which no longer recognizes the original Cat 5 specification. Although 1000BASE-T was designed for use with Cat 5 cable, the tighter specifications associated with Cat 5e cable and connectors allow it to be used with 1000BASE-T. Despite the stricter performance specifications, Cat 5e cable does not enable longer cable distances for Ethernet networks: cables are still limited to a maximum of 328 ft (100 m) in length. Cat 5e cable performance characteristics and test methods are defined in TIA/EIA-568-B.2-2001.

Category 6 cable, commonly referred to as Cat 6, is a cable standard for Gigabit Ethernet and other network protocols that is backward compatible with the Category 5/5e and 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. Cat-6 connectors are made to higher standards that help reduce noise caused by crosstalk and system noise. Attenuation, NEXT (Near End Crosstalk), and PSNEXT (Power Sum NEXT) are all significantly lower when compared to Cat-5/5e.

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 ANSI/TIA/EIA-568-B, the maximum allowed length of a Cat-6 horizontal cable is 100 meters (330 ft) in length, depending upon the ratio of cord length:horizontal cable length.

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

2/13/2008 SIIS – Level 3 Gregor Deans "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 . 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.

Category 7 cable (CAT7), (ISO/IEC 11801:2002 category 7/class F), is a cable standard for Ethernet and other interconnect technologies that can be made to be backwards compatible with traditional CAT5 and CAT6 Ethernet cable. CAT7 features even more strict specifications for crosstalk and system noise than CAT6. To achieve this, shielding has been added for individual wire pairs and the cable as a whole.

The CAT7 cable standard has been created to allow over 100 m of copper cabling. The cable contains four twisted copper wire pairs, just like the earlier standards. When combined with GG-45 or TERA connectors, CAT7 cable is rated for transmission frequencies of up to 600 MHz.

TIA and ISO Equivalent Classifications Frequency TIA ISO ISO TIA (Cabling) Bandwidth (Components) (Components) (Cabling) 1 - 100 MHz Category 5e Category 5e Category 5e Class D 1 - 250 MHz Category 6 Category 6 Category 6 Class E

1 - 500 MHz Category 6A Category 6A Category 6A Class EA 1 - 600 MHz n/s n/s Category 7 Class F

1 - 1,000 MHz n/s n/s Category 7A Class FA

TIA and ISO Standards References TIA Cabling Standards ANSI/TIA/EIA-568-B.2, Commercial Building Standard Category 5e Part 2: Balanced Twisted pair Cabling Components, 2001 ANSI/TIA/EIA-568-B.2-1, Commercial Building Telecommunications Standard, Part 2. Category 6 Addendum 1: Transmission Performance Specifications for 4 Pair 100 Ohm category 6 cabling, 2002 Category 6A ANSI/TIA/EIA-568-B.2-10, Commercial Building Telecommunications Standard, Part 2.

2/13/2008 SIIS – Level 3 Gregor Deans Addendum 10: Transmission Performance Specifications for 4 Pair 100 Ohm Augmented Category 6 Cabling, pending publication ISO Cabling Standards Class D ISO/IEC 11801, 2nd Ed., Information technology - Generic Cabling for Customer Premises, 2002 Class E ISO/IEC 11801, 2nd Ed., Information technology - Generic Cabling for Customer Premises, 2002 Amendment 1 to ISO/IEC 11801, 2nd Ed., Information technology - Generic Cabling for Customer Premises, pending Class E A publication Class F ISO/IEC 11801, 2nd Ed., Information technology - Generic Cabling for Customer Premises, 2002 Amendment 1 to ISO/IEC 11801, 2nd Ed., Information technology - Generic Cabling for Customer Premises, pending Class F A publication

Industry Standards Performance Comparison at 100 MHz for Channels Category 5e Class Category 6 Class Category 6A Class Class F Class FA D E EA Frequency Range (MHz) 1 - 100 1 - 250 1 - 500 1 - 600 1 - 1,000 Insertion Loss (dB) 24.0 21.3 (21.7) 20.9 20.8 20.3 NEXT Loss (dB) 30.1 39.9 39.9 62.9 65.0 PSNEXT Loss (dB) 27.1 37.1 37.1 59.9 62.0 ACR (dB) 6.1 18.6 18.6 42.1 46.1 PSACR (dB) 3.1 15.8 15.8 39.1 41.7 ACRF1) (dB) 17.4 23.3 23.3 (25.5) 44.4 47.4 PSACRF2) (dB) 14.4 20.3 20.3 (22.5) 41.4 44.4 Return Loss (dB) 10.0 12.0 12.0 12.0 12.0 PSANEXT Loss (dB) n/s n/s 60.0 n/s 67.0 PSAACRF (dB) n/s n/s 37.0 n/s 52.0 TCL (dB) n/s n/s 20.3 20.3 20.3 ELTCTL (dB) n/s n/s 0.5 (0) 3) 0 0 Propagation Delay (ns) 548 548 548 548 548 Delay Skew (ns) 50 50 50 30 30

1. Specified as ELFEXT for category 5e/class D and category 6/class E. 2. Specified as PSELFEXT for category 5e/class D and category 6/class E.

2/13/2008 SIIS – Level 3 Gregor Deans 3. ELTCTL is specified at 30 MHz.

Table provides comparative channel performance data at 100 MHz for category 5e/class D, category 6/classE, category 6A/class EA, class F, and class FA channels. Where there is a slight difference between TIA and ISO performance limits, ISO performance limits are indicated in parenthesis.

2/13/2008 SIIS – Level 3 Gregor Deans