Cisco Systems 15454 SDH 14.3.6.1 E-Series Multi-Instance Spanning Tree and VLANs

REVIEW DRAFT—CISCO CONFIDENTIAL
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Cisco ONS 15454 SDH Reference Manual, R5.0
April 2008
Chapter14 Ethernet Operation
14.3.6 E-Series Spanning Tree (IEEE 802.1D)
Figure14-15 Spanning Tree Map on the Circuit Window
Note Green represents forwarding spans and purple represen ts blocked (protect) spans. If you have a packet
ring configuration, at least one span should be purple.
Caution Multiple circuits with STP protection enabled will incur blocking if the circuits traverse a common card
and use the same VLAN.
Note E-Series port-mapped mode does not support STP (IEEE 8021. D).
14.3.6.1 E-Series Multi-Instance Spanning Tree and VLANs
The ONS 15454 SDH can operate multiple instances of STP to support VLANs in a looped topology.
You can dedicate separate circuits across the SDH ring for different VLAN groups. Each circuit runs its
own STP to maintain VLAN connectivity in a multiring environment.
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