MSTI Calculation
In an MST region, MSTP calculates an MSTI for each VLAN based on mappings between
VLANs and MSTIs. Each MSTI is calculated independently. The calculation process is similar
to the process for STP to calculate a spanning tree. For details, see
.
MSTIs have the following characteristics:
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The spanning tree is calculated independently for each MSTI, and spanning trees of MSTIs
are independent of each other.
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MSTP calculates the spanning tree for an MSTI in the manner similar to STP.
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Spanning trees of MSTIs can have different roots and topologies.
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Each MSTI sends BPDUs in its spanning tree.
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The topology of each MSTI is configured by using commands.
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A port can be configured with different parameters for different MSTIs.
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A port can play different roles or have different status in different MSTIs.
On an MSTP-aware network, a VLAN packet is forwarded along the following paths:
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MSTI in an MST region
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CST among MST regions
MSTP Responding to Topology Changes
MSTP topology changes are processed in the manner similar to that in RSTP. For details about
how RSTP processes topology changes, see
7.2.5 MSTP Fast Convergence
MSTP supports both ordinary and enhanced Proposal/Agreement (P/A) mechanisms:
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Ordinary P/A
The ordinary P/A mechanism supported by MSTP is implemented in the same manner as
that supported by RSTP. For details about the P/A mechanism supported by RSTP, see
.
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Enhanced P/A
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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