2-1

Chapter 2: Network Planning

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 on e of the
most important building blocks for 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. And, by using full-duplex mode, the bandwidth of the dedicate d
segment can be doubled to maximize throughput.
When networks are based on repeater (hub) technology, 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 manageabl e
segments, and linking them to the larger network by means of a switc h, removes this
limitation.
A switch can be easily configured in any Ethernet, Fast Ethernet, or Gigabit Ethernet
network to significantly boost bandwidth while using conventional cabling an d
network cards.