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extension of the 10BaseT Ethernet standard, designed to raise the data
transmission capacity of 10BaseT from 10Mbits/sec to 100Mbits/sec. An
important technology incorporated by 100BaseT is its use of the Carrier
Sense Multiple Access with Collision Detection (CSMA/CD) protocol -
which is the same protocol that 10BaseT uses - because of its ability to
work with several different types of cable, including basic twisted-pair
wiring. Both of these features play an important role in network
considerations, and they make 100BaseT an attractive migration path for
those networks based on 10BaseT. Since the 100Mbps Fast Ethernet is
compatible with all other 10Mbps Ethernet environments, it provides a
straightforward upgrade and takes advantage of the existing investment
in hardware, software, and personnel training.
Switching Technology
Switching is a cost-effective way of increasing the total network capacity
available to users on a LAN. If an Ethernet network begins to display
symptoms of congestion, low throughput, slow response times, and high
rates of collision, installing a switch to an network can preserve much or
all of the existing network's cabling and workstation interface card
infrastructure while still greatly enhancing the throughput for users. A
switch is a viable solution even if demanding applications, such as
multimedia production and video conferencing, are on the horizon. The
most promising techniques, as well as the best return on investment,
could well consist of installing the right mixture of Ethernet switches.
A switch increases capacity and decreases network loading by dividing a
local area network into different LAN segments. Dividing a LAN into
multiple segments is one of the most common ways of increasing
available bandwidth. If segmented correctly, most network traffic will
remain within a single segment, enjoying the full-line speed bandwidth of
that segment.
Switches provide full-line speed and dedicated bandwidth for all
connections. This is in contrast to the hubs, which use the traditional
shared networking topology, where the connected nodes contend for the
same network bandwidth. When two switching nodes are communicating,
they are connected with a dedicated channel between them, so there is
no contention for network bandwidth with other nodes. As a result, the
switch reduces considerably the likelihood of traffic congestion.
