Glossary
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SIGNAL QUALITY ERROR (SQE)—Also referred to as Collision or Collision
Presence. This occurs when two devices attempt to transmit at the same time, which is
an illegal condition. All ATI transceivers test for SQE.
SQE TEST—Commonly referred to as Heartbeat, is a special 802.3 signal sent by the
MAU to the DTE to test the collision detection function. Some DTE want SQE and
others do not. Repeaters do not want the SQE Test.
STRAIGHT-THROUGH—A type of wiring connection where the pins of one connector
connect to the same pins of another connector. For example, pin 1 of one connector
connects to pin 1 of another connector.
THICK ETHERNET—See 10Base5
THIN ETHERNET—See 10Base2
TRUNK CABLE—The coaxial cable used to distribute signals over long distances
throughout a cable system.
UNSHIELDED TWISTED PAIR (UTP)—A cable used in 10Base-T wiring that
consists of at least two twisted pairs of 22 to 26 AWG wire. The pairs should have at least
3 twists per foot and have an impedance of 100
Ω
. Level 3, Level 4 and Level 5 UTP
cables fit these criteria.