Dell S4048T - 33 Multiple Spanning Tree Protocol (MSTP); Protocol Overview

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.
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