Nortel Networks WEB OS 212777 - Manual (Page 54)

Web OS 10.0 Application Guide
54 n Chapter 2: VLANs
212777-A, February 2002
Switch-Centric Spanning Tree Protocol
In Figure 2-5 on page 53 , VLAN 2 is shared by Web switch A and B on ports 8 and 1 respec-
tively. Web switch A identifies VLAN 2 in Spanning Tree group 2 and Web switch B identifies
VLAN 2 in Spanning Tree group 1. Spanning Tree group is switch-centric—it is used to iden-
tify the VLANs participating in the Spanning Tree groups. The Spanning Tree group ID is not
transmitted in the BPDU. Each Spanning Tree decision is based on the configuration of that
switch.
Table 2-2 Multiple Spanning Tree Groups per VLAN
VLAN 1 VLAN 2 VLAN 3
Web Switch A Spanning Tree Group 1
Ports 1 and 2 Spanning Tree Group 2
Port 8
Web Switch B Spanning Tree Group 1
Port 1 Spanning Tree Group 2
Port 8
Web Switch C Spanning Tree Group 1
Ports 1 and 2 Spanning Tree Group 2
Port 8
Web Switch D Spanning Tree Group 1
Ports 1 and 8