Multiple Simultaneous Conversations; Figure 6. Multiple Conversations Through A Sts16-20Rm Or Sts16-20Frm Switch - Cabletron Systems SmartSTACK STS16-20RM Installation And User Manual

18

Multiple Simultaneous Conversations

A limitation of Token Ring is that it supports only one packet at a time. The STS16-
20RM and the STS16-20FRM 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 6. Multiple Conversations Through a STS16-20RM or
STS16-20FRM Switch
For example, as shown in Figure 6, 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.
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
SmartStack STS16-20RM/STS16-20FRM Token Ring Switches, P/N: 9032957-01 Switch Overview