Reference Guide

708 | Per-VLAN Spanning Tree Plus (PVST+)
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Figure 39-1. Per-VLAN Spanning Tree
Dell networking OS supports three other variations of Spanning Tree, as shown in Table 39-1.
Implementation Information
• The Dell networking OS implementation of PVST+ is based on IEEE Standard 802.1d.
• The Dell networking OS implementation of PVST+ uses IEEE 802.1s costs as the default costs
(Table 39-2). Other implementations use IEEE 802.1d costs as the default costs if you are using Dell
Networking systems in a multi-vendor network, verify that the costs are values you intended.
• On the S5000, you can enable PVST+ on 254 VLANs. To set up VLANs, see Chapter 54, Virtual
LANs (VLAN).
Table 39-1. Dell networking OS Supported Spanning Tree Protocols
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
R2
R3
R1
2/32
1/22
1/32
2/12
3/22
3/12
STI 3: VLAN 300
STI 1: VLAN 100
STI 2: VLAN 200STI 2: VLAN 200
Forwarding
X
X
X
X
X
X
STI 1/2/3 root
Blocking