Huawei AR530 Series - Page 241

Figure 7-4 MST region
D0
S1
other VLANs
MSTI0
S2
S4
S3
VLAN1 MSTI1
VLAN2,VLAN3 MSTI2
MSTI1
root switch:S3
MSTI2
root switch:S2
MSTI0 (IST)
root switch:S1
AP1
Master Bridge
VLAN Mapping Table
The VLAN mapping table is an attribute of the MST region. It describes mappings between
VLANs and MSTIs.
As shown in Figure 7-4, the mappings in the VLAN mapping table of the MST region D0 are
as follows:
l VLAN 1 is mapped to MSTI 1.
l VLAN 2 and VLAN 3 are mapped to MSTI 2.
l Other VLANs are mapped to MSTI 0.
Regional Root
Regional roots are classified into Internal Spanning Tree (IST) and MSTI regional roots.
In the region B0, C0, and D0 on the network shown in Figure 7-6, the switching devices closest
to the Common and Internal Spanning Tree (CIST) root are IST regional roots.
An MST region can contain multiple spanning trees, each called an MSTI. An MSTI regional
root is the root of the MSTI. On the network shown in Figure 7-5, each MSTI has its own
regional root.
Huawei AR530&AR550 Series Industrial Switch Routers
Configuration Guide - Ethernet Switching
7 MSTP Configuration
Issue 01 (2014-11-30) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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