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I
NTRODUCTION
This chapter describes the features of the Switch and some background information
about Ethernet/Fast Ethernet/Gigabit Ethernet switching technology.
Fast Ethernet Technology
The growing importance of LANs and the increasing complexity of desktop computing
applications are fueling the need for high performance networks. A number of high-
speed LAN technologies have been proposed to provide greater bandwidth and improve
client/server response times. Among them, 100BASE-T (Fast Ethernet) provides a non-
disruptive, smooth evolution from the current 10BASE-T technology. The non-
disruptive and smooth evolution nature, and the dominating potential market base,
virtually guarantee cost-effective and high performance Fast Ethernet solutions.
100Mbps Fast Ethernet is a standard specified by the IEEE 802.3 LAN committee. It is
an extension of the 10Mbps Ethernet standard with the ability to transmit and receive
data at 100Mbps, while maintaining the CSMA/CD Ethernet protocol. 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.
Gigabit Ethernet Technology
Gigabit Ethernet is an extension of IEEE 802.3 Ethernet utilizing the same packet
structure, format, and support for CSMA/CD protocol, full duplex, flow control, and
management objects, but with a tenfold increase in theoretical throughput over 100-
Mbps Fast Ethernet and a hundredfold increase over 10-Mbps Ethernet. Since it is
compatible with all 10-Mbps and 100-Mbps Ethernet environments, Gigabit Ethernet
provides a straightforward upgrade without wasting a company’s existing investment in
hardware, software, and trained personnel.
The increased speed and extra bandwidth offered by Gigabit Ethernet are essential to
coping with the network bottlenecks that frequently develop as computers and their
busses get faster and more users using applications that generate more traffic.
Upgrading key components, such as your backbone and servers to Gigabit Ethernet can
greatly improve network response times as well as significantly speed up the traffic
between your subnets.
Gigabit Ethernet supports video conferencing, complex imaging, and similar data-
intensive applications. Likewise, since data transfers occur 10 times faster than Fast
