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CAT 5 - ANSI/EIA (American National Standards Institute/Electronic
Industries Association) Standard 568 is one of several standards that specify
"categories" (the singular is commonly referred to as "CAT") of twisted pair
cabling systems (wires, junctions, and connectors) in terms of the data rates
that they can sustain. CAT 5 cable has a maximum throughput of 100 Mbps
and is usually utilized for 100BaseTX networks.
CAT 5e - The additional cabling performance parameters of return loss and far-
end crosstalk (FEXT) specified for 1000BASE-T and not specified for
10BASE-T and 100BASE-TX are related to differences in the signaling imple-
mentation. 10BASE-T and 100BASE-TX signaling is unidirectional-signals
are transmitted in one direction on a single wire pair. In contrast, Gigabit
Ethernet is bi-directional-signals are transmitted simultaneously in both direc-
tions on the same wire pair; that is, both the transmit and receive pair occupy
the same wire pair .
Data Packet - One frame in a packet-switched message. Most data communi-
cations is based on dividing the transmitted message into packets. For example,
an Ethernet packet can be from 64 to 1518 bytes in length.
Dynamic Routing - The ability for a router to forward data via a different route
based on the current conditions of the communications circuits. For example, it
can adjust for overloaded traffic or failing lines and is much more flexible than
static routing, which uses a fixed forwarding path.
Ethernet - IEEE standard network protocol that specifies how data is placed on
and retrieved from a common transmission medium. Has a transfer rate of 10
Mbps. Forms the underlying transport vehicle used by several upper-level proto-
cols, including TCP/IP and XNS.
Fast Ethernet - A 100 Mbps technology based on the 10BASE-T Ethernet
CSMA/CD network access method.
Full Duplex - The ability of a device or line to transmit data simultaneously in
both directions.
Half Duplex - Data transmission that can occur in two directions over a single
line, but only one direction at a time.
Hardware - Hardware is the physical aspect of computers, telecommunications,
and other information technology devices. The term arose as a way to distinguish
the "box" and the electronic circuitry and components of a computer from the pro-
gram you put in it to make it do things. The program came to be known as the soft-
ware.
EtherFast
®
10/100/1000 8-Port GigaSwitch
Glossary
10BaseT - An Ethernet standard that uses twisted wire pairs.
100BaseTX - IEEE physical layer specification for 100 Mbps over two pairs of
Category 5 UTP or STP wire.
1000BASE-T - provides half-duplex (CSMA/CD) and full-duplex 1000Mbps
Ethernet service over Category 5e links as defined by ANSI/TIA/EIA-568-A.
Topology rules for 1000BASE-T are the same as those used for 100BASE-TX.
Category 5e link lengths are limited to 100 meters by the ANSI/TIA/EIA-568-
A cabling standard. Only one CSMA/CD repeater will be allowed in a collision
domain.
Adapter - Printed circuit board that plugs into a PC to add to capabilities or
connectivity to a PC. In a networked environment, a network interface card
(NIC) is the typical adapter that allows the PC or server to connect to the
intranet and/or Internet.
Auto-negotiate - To automatically determine the correct settings. The term is
often used with communications and networking. For example, Ethernet
10/100 cards, hubs and switches can determine the highest speed of the node
they are connected to and adjust their transmission rate accordingly.
Backbone - The part of a network that connects most of the systems and net-
works together and handles the most data.
Bandwidth - The transmission capacity of a given facility, in terms of how
much data the facility can
transmit in a fixed amount of time; expressed in bits per second (bps).
CAT 3 - ANSI/EIA (American National Standards Institute/Electronic
Industries Association) Standard 568 is one of several standards that specify
"categories" (the singular is commonly referred to as "CAT") of twisted pair
cabling systems (wires, junctions, and connectors) in terms of the data rates
that they can sustain. CAT 3 cable has a maximum throughput of 16 Mbps and
is usually utilized for 10BaseT networks.
Instant Gigabit™ Series
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