LevelOne GSW-1676, User Manual

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RSTP
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alternate route that can be used when a node or port fails, and retaining the
forwarding database for ports insensitive to changes in the tree structure
when reconfiguration occurs.
Configuring RSTP
Use the RSTP Configuration page to specify global or port-specific
parameters for the Rapid Spanning Tree Protocol.
Field Attributes
RSTP System Configuration
• System Priority – Bridge priority is used in selecting the root device,
root port, and designated port. The device with the highest priority
becomes the STA root device. However, if all devices have the same
priority, the device with the lowest MAC address will then become the
root device. (Note that lower numeric values indicate higher priority.)
(Default: 32768; Range: 0-61440, in steps of 4096)
• Hello Time – Interval (in seconds) at which the root device transmits a
configuration message (BPDU frame).
(Default: 2;
Minimum: 1,
Maximum: The lower of 10 or [(Max. Message Age / 2) - 1])
• Max Age – The maximum time (in seconds) a device can wait without
receiving a configuration message before attempting to reconfigure. That
also means the maximum life time for a BPDU frame. All device ports
(except for designated ports) should receive configuration messages at
regular intervals. Any port that ages out STA information (provided in
the last configuration message) becomes the designated port for the
attached LAN. If it is a root port, a new root port is selected from among
the device ports attached to the network.
(Default: 20,
Minimum: The higher of 6 or [2 x (Hello Time + 1)],
Maximum: The lower of 40 or [2 x (Forward Delay - 1)])
• Forward Delay – The maximum time (in seconds) the root device will
wait before changing states (i.e., discarding to learning to forwarding).