Huawei quidway s7700 - Configuring a Proposal;Agreement Mechanism

l Configuring basic MSTP functions
Data Preparation
To configure MSTP interoperability between Huawei devices and non-Huawei devices, you
need the following data.
No. Data
1 BPDU format
2 MSTP protocol packet format
9.6.2 Configuring a Proposal/Agreement Mechanism
To enable Huawei Datacom devices to communicate with non-Huawei devices, configure a
proper rapid transition mechanism on Huawei devices according to the Proposal/Agreement
mechanism on non-Huawei devices.
Context
The rapid transition mechanism is also called the Proposal/Agreement mechanism. Switching
devices currently support the following modes:
l Enhanced mode: The current interface counts a root port when it computes the
synchronization flag bit.
– An upstream device sends a Proposal message to a downstream device, requesting rapid
status transition. After receiving the message, the downstream device sets the port
connected to the upstream device as a root port and blocks all non-edge ports.
– The upstream device then sends an Agreement message to the downstream device. After
the downstream device receives the message, the root port transitions to the Forwarding
state.
– The downstream device then responds to the Proposal message with an Agreement
message. After receiving the message, the upstream device sets the port connected to
the downstream device as a designated port, and the designated port transitions to the
Forwarding state.
l Common mode: The current interface ignores the root port when it computes the
synchronization flag bit.
– An upstream device sends a Proposal message to a downstream device, requesting rapid
status transition. After receiving the message, the downstream device sets the port
connected to the upstream device as a root port and blocks all non-edge ports. The root
port then transitions to the Forwarding state.
– The downstream device responds to the Proposal message with an Agreement message.
After receiving the message, the upstream device sets the port connected to the
downstream device as a designated port. The designated port then transitions to the
Forwarding state.
When Huawei Datacom devices are interworking with non-Huawei devices, select either mode
depending on the Proposal/Agreement mechanism on non-Huawei devices.
Quidway S7700 Smart Routing Switch
Configuration Guide - Ethernet 9 MSTP Configuration
Issue 01 (2011-07-15) Huawei Proprietary and Confidential
Copyright © Huawei Technologies Co., Ltd.
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