Spanning Tree Protocol Parameters
Spanning Tree Concepts A-3
A.3 SPANNING TREE PROTOCOL PARAMETERS
Several configuration parameters control the operation of the Spanning Tree Protocol. Table A- 1
describes the parameters and lists the swit ch default settings for each parameter.
NOTE: You can cause serious network performance degradation if you do not fully
understand Spanning Tree concepts. Be sure to consult personnel experienced with this
process prior to configuring Spanning Tree parameters.
Table A-1 Spanning Tree Protocol Defaults
Parameter Descriptio n Default Value
Bridge Group
Address
Unique MAC group address, recognized by all bridges in
the network.
None
Bridge
Identifier
Identifier for each bridge. This parameter consists of two
parts: a 16-bit bridge priority and a 48-bit network adapter
address. Ports are numbered in absolute numbers starting
from 1 regardless of their bridge attachment. The network
adapter address is the same address as the first port of the
bridge.
32768 (bridge
priority)
Port Identifier Identifies each port of each bridge, with an incremental
default value given for each port.
Port 1 -32768 Port 9 -32776 Port17-32784
Port 2 -32769 Port 10 -32777 Port 18 -32785
Port 3 -32770 Port 11 -32778 Port 19 -32786
Port 4 -32771 Port 12 -32779 Port 20 -32787
Port 5 -32772 Port 13 -32780 Port 21 -32788
Port 6 -32773 Port 14 -32781 Port 22 -32789
Port 7 -32774 Port 15 -32782 Port 23 -32790
Port 8 -32775 Port 16 -32783 Port 24 -32791
Port Priority Indicates the priority of a specific port in relation to
other ports.
128