Cat (Category)

A set of structured cabling standards have been developed over time by standards bod-

ies acting in various collaborations. The standards bodies are the American National Standards Institute (ANSI), Electronic Industries Alliance (EIA), Insulated Cable Engineers Association (ICEA), International Electrotechnical Commission (IEC), International Organization for Standardization (ISO), and Telecommunications Industry Association (TIA). EIA/TIA 568A, released in 1985, built on earlier work at AT&T, IBM, and other companies, and set the tone for formally standardization structured wiring standards.That standard subsequently was supplemented and improved as EIA/TIA 568B. It also was internationalized in 1995 as ISO/IEC 11801.The standards are known as Cat 1, Cat 2, Cat 3, Cat 4, Cat 5, Cat 6, and Cat 7, and are progressively more capable due to tighter tolerances on dimensions and different twist pitches.

Table C-1 compares the various categories with gauge measurements stated in American Wire Gauge (AWG). See also ANSI, AWG, Cat 1-7, EIA, EIA/TIA- 568, ICEA, IEC, ISO, ISO/IEC 11801, TIA, and twist pitch.

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• 1A2
• 1Base5 (1 Mbps; Baseband; 500 meters)
• 1B+D
• 1. Domain Name System. The naming convention that divides the Internet into logical domains identified in Internet Protocol version 4 (IPv4) as a 32-bit portion of the total address.The standard convention is user@organization.domain, where user is the name of the end user, organization is the name of the enterprise or other organization owning or sponsoring the address, and domain is the type of entity owning or sponsoring the address.The administration of the DNS is the responsibility of Internet Corporation for Assigned Names and Numbers (ICANN). See also domain, ICANN, Internet, and IPv4. 2.
• 1. In storage, irrelevant material, usually zero (0) bits, added to a data block in order to fill it to a minimum size, to force certain fields of control data or user data into certain positions or sizes, or to prevent the user data from duplicating a bit pattern that has a specific control meaning. See also block. 2.
• 1 cps, 1 Hz
• 1+ Dialing
• 1G (1st Generation)
• 1G (1st Generation)
• 1-persistent carrier sense multiple access (1-Persistent CSMA)
• 1-Persistent CSMA (1-Persistent Carrier Sense Multiple Access)
• 1+ WATS
• 1xEV-DO (one carrier EVolution-Data Optimized)
• 1xRTT (one times Radio Transmission Technology)
• 2
• 20
• 2:1
• 2:1
• 2:1
• 218–219 MHz Service
• 22
• 23B+D
• 23B+D
• 24
• 256-QAM