The rapid transition mechanism is also called the Proposal/Agreement mechanism. All switches support the following modes:
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 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.
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 devices are connected to non-Huawei devices, select the same mode as that used on non-Huawei devices.