Fujitsu Siemens Computers PRIMERGY BX, Description

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Introduction to Switching Network Planning
Lan Switch and Router Blade
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3 Network Planning
3.1 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 for
today’s networking technology.
When performance bottlenecks are caused by congestion at the network access point
(e.g., the network card for a high-volume file server), the device experiencing the congestion
(e.g., a server or user) can be attached directly to a switched port. This allocates the full
bandwidth of the Ethernet segment to the devices attached to a single port on the switch. And,
when operating at full- duplex, the bandwidth of the dedicated segment can be doubled to
further maximize throughput.
When networks are based on repeater (hub) technology, the maximum distance between
end stations is limited. For traditional Ethernet, there may be up to four hubs between any pair
of stations; for Fast Ethernet, the maximum is two. This is known as the hop count. However, a
switch turns the hop count back to zero, subdividing the network into smaller and more
manageable segments, and linking them to the larger network by means of a switch, thereby
removing this limitation.
The Switch Blade can be easily configured into any Ethernet network to signifi- cantly boost
bandwidth, while using conventional cabling and network cards.