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HAPTER

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ETWORK

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LANNING

Introduction to Switching

A network switch allows simultaneous transmission of multiple packets via
non-crossbar switching. This means that it can partition a network more
efficiently than bridges or routers. The switch has, therefore, been
recognized as one of the most important building blocks fo r today’s
networking technology.
When performance bottlenecks are caused by congestion at the network
access point (such as the network card for a high-volume file server), the
device experiencing congestion (server, power user, or hub) can be
attached directly to a switched port. By usin g full-duplex mode, the
bandwidth of the dedicated segment can be doubled to maximize
throughput.
When networks are based on repeater (hub) technolog y, the distance
between end stations is limited by a maximum hop count. However, a
switch turns the hop count back to zero. So subdividing the network into
smaller and more manageable segments, and linking them to the larger
network by means of a switch, removes this limitation.
A switch can be easily configured in any network to significantly boost
bandwidth while using conventional cabling and network cards.