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2 - Bridge Priority
The Bridge Priority option specifies the bridge's priority for becoming the Root Bridge. The bridge with the lowest bridge
priority is elected to be the Root Bridge.
Default:
[32768] * (IEEE 802.1D recommendation)
Range:
0 to 65535
Considerations:
* This value is the first part of the Bridge ID For example: 32768-0000d0111111
If you want the bridges to decide among themselves which is to be the Root bridge, then set all bridges'
bridge priorities to the IEEE 802.1D default 32768. In this instance, with all bridge priorities being the same,
the bridge with the lowest MAC address will be chosen as the Root Bridge.
Lower Value
If you want this bridge to become the Root Bridge, then set this number to be lower than the other bridges
in the network.
Higher Value
If you want this bridge to become blocked (become the standby bridge where a redundant path exists), then
set this number higher than the other bridge(s) competing to be the designated bridge for a LAN.
3 - Forwarding Delay
During a change in topology, the Forwarding Delay value specifies the time the bridge will wait in each of the Listening
and Learning States before forwarding of frames begins.
In the Listening State, the bridge "listens" for the other bridges' topology and configuration information. (Non-
permanent addresses are aged-out and cleared from the address table before the Learning State is entered.)
In the Learning State, the bridge learns the addresses of as many stations as possible, so when entering the Forwarding State
it avoids flooding the network with packets destined for unknown addresses.
During the Listening and Learning State intervals, forwarding is blocked although during the Learning State, learned
station information is included in the address table.
Default:
[15 sec] (IEEE 802.1D recommendation)
Range:
4 to 30 seconds
Considerations:
The Forwarding Delay time of the bridge is applicable only if the bridge is, or becomes, the Root bridge,
since the Root values override a non-root's Forwarding delay time value. The Root value is known as the
Network Forward(ing) Delay.
Lower Value
If this bridge is the Root, or becomes the Root, setting the Forwarding Delay to a lower value might cause
the network to flood with packets destined for addresses not yet learned. During the Listening State, the Root
Bridge might also miss another bridge's information about a Topology Change if the Forwarding Delay is set
too low.
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