3Com PS Hub 40, User Manual

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DUA1640-5AAA02
PS Hub 50 2-5
Fast Ethernet Resilience
The process that chooses the active switch (when there are multiple
PS Hub 50 units in a stack) enables you to have a Fast Ethernet resilient
link in your stack.
Figure 2-2 shows a stack of two PS Hub 50 units, both with 100Mbps
transceiver modules. Both transceiver modules have a connection and
appear to be equal, so the bottom unit’s segment is the active segment
switch (and that transceiver module is used). If the connection to the
bottom unit’s transceiver module fails, the stack reconfigures so that
the top unit’s segment switch becomes the active segment switch.
Figure 2-2
Fast Ethernet Resilience