MicroNet SP648B, Руководство пользователя

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100Mbps Fast Ethernet is a standard specified by the IEEE 802.3 LAN committee. It is
an extension of the 10Mbps Ethernet standard with the ability to transmit and receive data
at 100Mbps, while maintaining the CSMA/CD Ethernet protocol. Since the 100Mbps Fast
Ethernet is compatible with all other 10Mbps Ethernet environments, it provides a
straightforward upgrade and takes advantage of the existing investment in hardware,
software, and personnel training.
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.
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 a router, the setup and maintenance
required make routers relatively impractical. Today switches are an ideal solution to most
kinds of local area network congestion problems.