3
Switching Technology
Another approach to pushing beyond the limits of Ethernet technology is the
development of switching technology. A switch bridges Ethernet packets at
the MAC address level of the Ethernet protocol transmitting among
connected Ethernet or Fast Ethernet LAN segments.
Switching is a cost-effective way of increasing the total network capacity
available to users on a local area network. A switch increases capacity and
decreases network loading by dividing a local area network into different
segments
, which don’t compete with each other for network transmission
capacity.
The switch acts as a high-speed selective bridge between the individual
segments. The switch, without interfering with any other segments,
automatically forwards traffic that needs to go from one segment to another.
By doing this the total network capacity is multiplied, while still maintaining
the same network cabling and adapter cards.
For Fast Ethernet networks, a switch is an effective way of eliminating
problems of chaining hubs beyond the “two-repeater limit.” A switch can be
used to split parts of the network into different collision domains, making it
possible to expand your Fast Ethernet network beyond the 205-meter network
diameter limit for 100BASE-TX networks. Switches supporting both
traditional 10Mbps Ethernet and 100Mbps Fast Ethernet are also ideal for
bridging between the existing 10Mbps networks and the new 100Mbps
networks.
Switching LAN technology is a marked improvement over the previous
generation of network bridges, which were characterized by higher latencies.
Routers have also been used to segment local area networks, but the cost of
setup and maintenance required make routers relatively impractical. Today
switches are an ideal solution to most kinds of local area network congestion
problems.
