Category 5 Cable

Category 5 cable, commonly known as Cat 5 or "Cable and
Telephone", is a twisted pair cable type designed for
high signal integrity. Many such cables are unshielded
but some are shielded. Category 5 has been superseded by
the Category 5e specification. This type of cable is
often used in structured cabling for computer networks
such as Ethernet, and is also used to carry many other
signals such as basic voice services, token ring, and
ATM (at up to 155 Mbit/s, over short distances).The specification for category 5 cable was defined in
ANSI/TIA/EIA-568-A, with clarification in TSB-95. These
documents specified performance characteristics and test
requirements for frequencies 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 Ethernet, although IEEE 802.3ab defines
standards for 1000BASE-T - Gigabit Ethernet 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.