Cisco Systems 15454 SDH 14.3.6.2 Spanning Tree on a Circuit-by-Circuit Basis, 14.3.6.3 E-Series Spanning Tree Parameters, 14.3.6.4 E-Series Spanning Tree Configuration

REVIEW DRAFT—CISCO CONFIDENTIAL
14-18
Cisco ONS 15454 SDH Reference Manual, R5.0
April 2008
Chapter14 Ethernet Operation
14.3.6 E-Series Spanning Tree ( IEEE 802.1D)
14.3.6.2 Spanning Tree on a Circuit-by-Circuit Basis
You can also disable or enable STP on a circuit-by-circuit basis on single-card EtherSwitch E-Series
cards in a point-to-point configuration. This feature allows custom ers to mix spanning tree protected
circuits with unprotected circuits on the same card. It also allows two single-card EtherSw itch E-Series
cards on the same node to form an intranode circuit.
14.3.6.3 E-Series Spanning Tree Parameters
Default STP parameters are appropriate for most situations (Table 14-2). Contact the Cisco Technical
Assistance Center (Cisco TAC) before you change the default STP parameters.
14.3.6.4 E-Series Spanning Tree Configuration
To view the spanning tree configuration, at the node view click the Provisioning > Etherbridge >
Spanning Trees tabs. (Table14-3).
Table14-2 Spanning Tree Parameters
Parameter Description
BridgeID ONS 15454 SDH unique identifier that transmits the configuration bridge protoc ol
data unit (BPDU); the bridge ID is a combination of the bridge priority and the
ONS 15454 SDH MAC address
TopoAge Amount of time in seconds since the last topology chan ge
TopoChanges Number of times the STP topology has been changed since the node booted up
DesignatedRoot STP’s designated root for a particular STP instance
RootCost Total path cost to the designated root
RootPort Port used to reach the root
MaxAge Maximum time that received-protocol information is retained before it is
discarded
HelloTime Time interval, in seconds, between the transmission of configuration BPDUs by a
bridge that is the spanning tree root or is attempting to become the spanning tree
root
HoldTime Minimum time period, in seconds, that elapses during the transmission of
configuration information on a given port
ForwardDelay Time spent by a port in the listening state and the learning state
Table14-3 Spanning Tree Configuration
Column Default Value Value Range
Priority 32768 0 to 65535
Bridge max age 20 seconds 6 to 40 seconds
Bridge Hello Time 2 seconds 1 to 10 seconds
Bridge Forward Delay 15 seconds 4 to 30 seconds