Olicom CrossFire 8600, Руководство по эксплуатации

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CrossFire 8600/8605 Token-Ring Switches v. 1.2, P/N: 710001641 Switch Theory of Operation
Multiple Simultaneous Conversations
A limitation of Token-Ring is that it supports only one packet at a time. The
CrossFire 8600 and the CrossFire 8605 improve data throughput by supporting
multiple, simultaneous, full-duplex conversations. By using High-Speed bus
switching technology, the switch creates multiple data paths. These switched
connections between Token-Ring segments last only for the duration of a byte
transmission. New connections are made “on-the-fly” between different ports on
the switch for the next byte.
Figure 5. Multiple Conversations Through a CrossFire 8600 or
CrossFire 8605 Switch
For example, as shown in Figure 5, while host A is transmitting a byte to host B,
the switch connects only the lines from A to B since there is no need to send packets
to all other ports. At the same time, a second switching circuit can connect host C
to host D. The result: Two packets are sent simultaneously.
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Note: The switch transmits broadcast and multicast packets on several switch ports
simultaneously.
The increase in throughput is directly proportional to the number of physical token-
rings that are interconnected through the switch. A switch with 20 ports
interconnected provides up to ten concurrent paths. With ten simultaneous