Increasing Network Bandwidth; High-Speed Backbones And Servers - D-Link DES-1008D User Manual

10/100 Dual-Speed Switch User's Guide

Increasing Network Bandwidth

A switch is capable of receiving and forwarding transmissions for
more than one port at the same time. In the case of half-duplex
ports which can either send or receive data, the switch can handle
transmissions from up to half of its ports (since the other half are
presumably receiving). In the case of full-duplex ports which can
send and receive at the same time, the switch can handle
simultaneous transmissions from all of its ports.
When a switch is handling two transmissions simultaneously, it
actually increases the bandwidth of the network. If, for example, a
switch is simultaneously transferring data from two 100 Mbps
ports to two other ports, the switch is handling 200 Mbps of traffic.
The switch has effectively doubled the overall network capacity. If
the ports are using full-duplex connections and the receiving ports
are simultaneously transmitting, then the switch is handling 400
Mbps of data, doubling the overall network bandwidth once again.
A switch that can process simultaneous full-duplex traffic from all
of its ports is able to operate at full wire speed. The total amount of
traffic a switch can handle is called the aggregate bandwidth.
This multiplication of network bandwidth allows high-speed,
collision-free communications between different network segments
that are interconnected through the switch.

High-speed Backbones and Servers

The ability of switches to support high-bandwidth, full-duplex,
collision-free connections makes them perfect for interconnecting
network segments, in other words, operating as the backbone of
the network. Full-duplex Fast Ethernet switch to switch
connections operate at 200 Mbps. Network servers (or any other
computer) using full-duplex Fast Ethernet NIC's can also have a
200 Mbps collision-free connection to the network.
5
Introduction