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100VG AnyLAN designed to handle speed with safety

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Why you can trust SCMP
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A traffic engineer, trying to relieve congestion on the streets of Hong Kong or any other major city in Asia, can usually apply several techniques to the problem. Trying to get the vehicles to speed up without widening the roads or improving traffic management is obviously not one of them as this would lead to an increase in collisions, resulting in even worse congestion.

The 'just speed up the cars' approach, however, is a perfect analogy of what happens to a network based on 100Base-T Fast Ethernet technology.

100VG AnyLAN, on the other hand, has been engineered to handle increased network speeds in safety. In any discussion of the two high-speed LAN technologies there are several other comparisons to be made, but the collision factor is the critical one.

To better understand the collision factor you need to look at the core technology used by the original Ethernet specification and 100Base-T. The Carrier Sense Multiple Access/Collision Detection (CSMA/CD) protocol is a'blind driving' system under which a network node can send data packets down the wire without reference to what the other nodes are up to.

At 10 megabits per second (Mbps) this simple system works reasonably well. The time taken to detect, clear up and re-send after a packet is not too much of a problem because network traffic moves relatively slowly.

At 100 Mbps, the window of opportunity for doing this is one-tenth the size, and, as a result, the network has to be physically smaller.

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