Specifications

Functions
RS2-4R
Release 1.0 03/04
4.4 Spanning Tree Algorithm
111
U Port statuses
According to the tree structure and the status of the selected connection
routes, RSTP assigns their statuses to the ports.
U Spanning Tree Priority Vector
To assign roles to ports, the RSTP bridges exchange configuration
information between themselves. This information is known as a
"Spanning Tree Priority Vector". It contains the following elements:
D Bridge identification of the root bridge
D Root path costs of the transmitting bridge
D Bridge identification of the transmitting bridge
D Port identification of the port through which the message was sent
D Port identification of the port through which the message was received
Based on this information, the bridges involved in the RSTP are capable
of calculating port roles by themselves and defining the port status of
their own ports.
STP Port State
Administrative
Bridge Port State
MAC
Operational
RSTP Port
State
Active Topology (Port Role)
DISABLED Disabled FALSE Discarding* Excluded (Disabled)
DISABLED Enabled FALSE Discarding** Excluded (Disabled)
BLOCKING Enabled TRUE Discarding* Excluded (Alternate, Backup)
LISTENING Enabled TRUE Discarding* Included (Root, Designated)
LEARNING Enabled TRUE Learning Included (Root, Designated)
FORWARDING Enabled TRUE Forwarding Included (Root, Designated)
Table 8: Relationship between the port-status values in the STP and RSTP
* The dot1d-MIB displays "Disabled"