User’s Manual of
Switch
Blocking
ListeningDisable
Learning
Forwarding
Figure 4-7-1 STP Port State Transitions
You can modify each port state by using management software. When you enable STP, every port on every switch in the network goes through the blocking state and then transitions through the states of listening and learning at power up. If properly configured, each port stabilizes to the forwarding or blocking state. No packets (except BPDUs) are forwarded from, or received by, STP enabled ports until the forwarding state is enabled for that port.
2.STP Parameters STP Operation Levels
The Switch allows for two levels of operation: the switch level and the port level. The switch level forms a spanning tree consisting of links between one or more switches. The port level constructs a spanning tree consisting of groups of one or more ports. The STP operates in much the same way for both levels.
On the switch level, STP calculates the Bridge Identifier for each switch and then sets the Root
Bridge and the Designated Bridges.
On the port level, STP sets the Root Port and the Designated Ports.
The following are the
Parameter | Description | Default Value |
Bridge Identifier(Not user | A combination of the | 32768 + MAC |
configurable | the switch’s MAC address. |
|
except by setting priority | The Bridge Identifier consists of two parts: |
|
below) | a |
|
| address 32768 + MAC |
|
|
|
|
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