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(Rapid) Spanning Tree
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Figure 5-18 Example 2 of the “relevant path”
5.2.5.10 Reconfiguration times
The reconfiguration time for a Spanning Tree depends on the timer values for MaxAge and
Forward Delay.
The minimum reconfiguration time is: 2 × Forward Delay
The maximum reconfiguration time is: 2 × Forward Delay + MaxAge
For the values recommended by the IEEE standard, the value for ten active STP switches
along a path beginning with the root switch is between 30 s and 50 s.
Switch-over time response to be expected for RSTP and RSTP with activated ring
detection
When using RSTP, expect switch-over times in the range from 100 ms to 2 s.
When using fast ring detection, expect switch-over times in the range from 100 ms to
500 ms.
The various roles of ports
The root port of a switch connects this switch to the root switch - either directly or via an-
other switch (designated switch).
The designated port is the port at a designated switch that is connected to the root port of
the next switch.
No additional switches/bridges are connected to an edge port. Termination devices are
connected to an edge port.
An alternate port is a path to the root, which, however, did not become a root port. This
means that this port is not part of the active topology.