Multiple Spanning Tree Protocol (MSTP)
Multiple spanning tree protocol (MSTP) — specified in IEEE 802.1Q-2003 — is a rapid spanning tree protocol (RSTP)-based spanning tree
variation that improves per-VLAN spanning tree plus (PVST+). MSTP allows multiple spanning tree instances and allows you to map many
VLANs to one spanning tree instance to reduce the total number of required instances.
Protocol Overview
MSTP — specified in IEEE 802.1Q-2003 — is a rapid spanning tree protocol (RSTP)-based spanning tree variation that improves on per-
VLAN spanning tree plus (PVST+). MSTP allows multiple spanning tree instances and allows you to map many VLANs to one spanning tree
instance to reduce the total number of required instances.
In contrast, PVST+ allows a spanning tree instance for each VLAN. This 1:1 approach is not suitable if you have many VLANs, because each
spanning tree instance costs bandwidth and processing resources.
In the following illustration, three VLANs are mapped to two multiple spanning tree instances (MSTI). VLAN 100 traffic takes a different
path than VLAN 200 and 300 traffic. The behavior demonstrates how you can use MSTP to achieve load balancing.
Figure 81. MSTP with Three VLANs Mapped to TWO Spanning Tree Instances
Topics:
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Configure Multiple Spanning Tree Protocol
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Multiple Spanning Tree Protocol (MSTP)
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Summary of Contents for S3048-ON
Page 1: ...Dell Configuration Guide for the S3048 ON System 9 11 2 5 ...
Page 137: ...0 Gi 1 1 Gi 1 2 rx Flow N A N A 0 0 No N A N A yes Access Control Lists ACLs 137 ...
Page 142: ...Figure 10 BFD Three Way Handshake State Changes 142 Bidirectional Forwarding Detection BFD ...
Page 241: ...Dell Control Plane Policing CoPP 241 ...
Page 287: ... RPM Synchronization GARP VLAN Registration Protocol GVRP 287 ...
Page 428: ...Figure 53 Inspecting the LAG Configuration 428 Link Aggregation Control Protocol LACP ...
Page 477: ...Figure 73 Configuring Interfaces for MSDP Multicast Source Discovery Protocol MSDP 477 ...
Page 478: ...Figure 74 Configuring OSPF and BGP for MSDP 478 Multicast Source Discovery Protocol MSDP ...
Page 483: ...Figure 77 MSDP Default Peer Scenario 2 Multicast Source Discovery Protocol MSDP 483 ...
Page 484: ...Figure 78 MSDP Default Peer Scenario 3 484 Multicast Source Discovery Protocol MSDP ...
Page 745: ...Figure 104 Single and Double Tag TPID Match Service Provider Bridging 745 ...
Page 746: ...Figure 105 Single and Double Tag First byte TPID Match 746 Service Provider Bridging ...