Spanning Tree Priority Vector - Hirschmann RS20 User Manual

Spanning Tree
STP port state Administrative
bridge port
state
DISABLED Disabled
DISABLED Enabled
BLOCKING Enabled
LISTENING Enabled
LEARNING Enabled
FORWARDING Enabled
Table 12: Relationship between port state values for STP and RSTP.
a. The dot1d-MIB displays "Disabled"
b. The dot1d-MIB displays "Blocked"
Meaning of the RSTP port states:

Disabled: Port does not belong to the active topology
 Discarding: No address learning in FDB, no data traffic except for BPDUs

Learning: Address learning active (FDB) and no data traffic except for
BPDUs
 Forwarding: Address learning is active (FDB), sending and receipt of all
frame types (not only BPDUs)
5.6.3

Spanning Tree Priority Vector

To assign roles to the ports, the RSTP bridges exchange configuration
information with each other. This information is known as the Spanning Tree
Priority Vector. It is part of the RSTP BPDUs and contains the following
information:
 Bridge identification of the root bridge

Root path costs of the sending bridge
 Bridge identification of the sending bridge
 Port identifiers of the ports through which the message was sent

Port identifiers of the ports through which the message was received
UM Redundancy Configuration L2E
Release 7.1 12/2011
MAC RSTP
operational Port state
FALSE Discarding
FALSE Discarding
TRUE Discarding
TRUE Discarding
TRUE Learning
TRUE Forwarding
5.6 The Rapid Spanning Tree
Active topology
(port role)
a
Excluded (disabled)
a
Excluded (disabled)
b
Excluded (alternate, backup)
b
Included (root, designated)
Included (root, designated)
Included (root, designated)
Protocol
75