CentreCOM
AT-3012T Multiport Repeater
19
PUNCH-DOWN BLOCK
—The punch-down block is the wiring panel
where the house wiring from the building’s offices terminates. This is where
many 10BASE-T hubs would be located. Wiring installers use a special
punch-down tool to insert the UTP wire for data and voice applications.
REPEATER
—A device used to extend the length, topology, or
interconnectivity of the physical medium beyond that imposed by a single
segment, up to the maximum allowable end-to-end trunk transmission line
length. Repeaters perform the basic actions of restoring signal amplitude,
waveform and timing applied to normal data and collision signals.
RJ45
—This connector is a 10BASE-T standard for connecting UTP cabling.
They are inexpensive and easy to install onto UTP cable.
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.
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 SQE Test.
THICK ETHERNET
—See 10BASE5
THIN ETHERNET
—See 10BASE2
TRUNK CABLE
—The trunk coaxial 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 and Level 4 UTP cable generally fits these criteria.
