Motorola RFS7000 Series System Reference Manual page 210

4-124 Network Setup
CIST Bridge HelloTime Set the CIST Hello Time (in seconds). After the defined interval all
Bridge Hello Time
CIST Bridge Forward
Delay
CIST Bridge Forward
Delay
CIST Bridge Maximum
Age
Bridge Maximum Age Enter the bridge maximum value.
bridges in a bridged LAN exchange BPDUs.
The hello time is the time interval (in seconds) the device waits
between BPDU transmissions.
If this is the root bridge, the value is equal to the configured Hello
Time.
A very low value leads to excessive traffic on the network, whereas
a higher value delays the detection of a topology change. This
value is used by all instances.
Displays the configured Hello Time.
Enter the CIST bridge forward delay value received from the root
bridge. If this is the root bridge, the value will be equal to the
Configured Forward Delay.
The forward delay value is the maximum time (in seconds) the root
device waits before changing states (from a listening state to a
learning state to a forwarding state).
This delay is required, as every device must receive information
about topology changes before forwarding frames.
In addition, each port needs time to listen for conflicting
information that would make it return to a blocking state;
otherwise, temporary data loops may result.
Displays the configured forward delay period.
Enter the CIST bridge maximum age received from the root bridge.
If this is the root bridge, the value will be equal to the Configured
Max Age.
The max-age is the maximum time (in seconds) for which (if a
bridge is the root bridge) a message is considered valid. This
prevents the frames from looping indefinitely. The max-age should
be greater than twice the value of hello time plus one, but less than
twice the value of forward delay minus one. The allowable range
for max-age is 6-40 seconds. Configure this value sufficiently high,
so a frame generated by root can be propagated to the leaf nodes
without exceeding the max-age.