Lantronix LTR8T, Installation Manual

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LTR-T Installation Guide 21
normal data and collision signals. The LTR-T is an example of a repeater, and the
physical medium that it uses is unshielded twisted-pair (UTP).
Segment
A length of coaxial or UTP cable. The LTR-T passes signals from each of its segments to
all other attached segments. A segment must be terminated at both ends, either via
terminators (10BASE2, 10BASE5) or devices (10BASE-T).
Tap
A tap usually refers to a physical connection to the network where other devices can be
attached. Taps may be of several types, including BNC taps, simple “T” taps, or
Thickwire Vampire taps that attach directly to a network cable and “inject” signals into
the cable.
Thickwire (10BASE5) Ethernet
This is also known as standard Ethernet. It specifies the physical layer according to IEEE
802.3, 10BASE5. It is thick coaxial cable, specified as 50 ohm RG10 cable. Thickwire
Ethernet has stricter rules for network configurations to allow the maximum transmission
distance of 500 meters.
Thinwire (10BASE2) Ethernet
An alternative physical layer for Ethernet specified as IEEE 802.3, 10BASE2. It is a
more flexible cable than Thickwire Ethernet with less stringent rules for attaching to the
cable. Maximum segment length is 185 meters. It is specified as 50 ohm RG58 cable
and is often referred to as “Cheapernet.”
Transceiver
In general, a device used to connect a network node/device to the Ethernet media. It
passes signals between the Ethernet and the AUI port, performing necessary interface
functions. For example, the LTX-2 attaches to Thinwire media, the LTX-5 attaches to
Thickwire , and the LTX-T attaches to unshielded twisted pair (UTP) cable.
Transceiver Cable
See Attachment Unit Interface (AUI) cable.
Unshielded Twisted Pair (UTP)
The physical layer medium referred to by the IEEE 802.3 10BASE-T specification.
Unshielded twisted pair cable consists of wires that are twisted together in pairs and
enclosed within a single jacket. In general, existing telephone cable can be used if it is of
high enough quality to support high-speed communications. Common UTP cable
provides 4 pairs of wires, thus can support two 10BASE-T connections. Each segment
can be a maximum of 100 meters long.