Extreme Networks ExtremeWare XOS Guide Manual page 445

As shown in Figure 43, after the configuration update, bridge D:
Moves the alternate port to a designated port.
●
Sends a "propose" message to bridge E to solicit confirmation of its designated role and to
●
rapidly move the port into the designated state.
Figure 43: Sending a propose message to confirm a port role
A
A , 0
F
E , 1
5 Upon receiving the proposal, bridge E (as shown in
Performs a configuration update.
●
Changes its receiving port to a root port.
●
The existing designated port enters the blocking state.
Bridge E then sends:
A "propose" message to bridge F.
●
An "agree" message from its root port to bridge D.
●
Figure 44: Communicating port status to neighbors
A
A , 0
F
E , 1
ExtremeWare XOS 11.3 Concepts Guide
B
A , 1
Designated
E
E , 0
Propose BPDU
B
A , 1
Designated
port
E
A , 4
Agree BPDU
C
A , 2
port
Root
port
D
A , 3
Figure 44):
C
A , 2
Root
port
D
A , 3
Rapid Spanning Tree Protocol
EX_055e
EX_055f
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