Dell PowerEdge FN I/O Module Configuration Guide 9.10(0.0)

PVST+ is a variation of spanning tree — developed by a third party — that allows you to configure a separate spanning tree instance for each virtual local area network (VLAN).

For more information about spanning tree, refer to the Spanning Tree Protocol (STP) chapter.

Figure 1. Per-VLAN Spanning Tree

The Dell Networking operating system (OS) supports three other variations of spanning tree, as shown in the following table.

Table 1. Spanning Tree Variations Dell Networking OS Supports

Dell Networking Term	IEEE Specification
Spanning Tree Protocol (STP)	802 .1d
Rapid Spanning Tree Protocol (RSTP)	802 .1w
Multiple Spanning Tree Protocol (MSTP)	802 .1s
Per-VLAN Spanning Tree Plus (PVST+)	Third Party