Configuring a Proposal/Agreement Mechanism

The rapid transition mechanism is also called the Proposal/Agreement mechanism. All switching devices support the following modes:

• Enhanced mode: The current interface includes the root port calculation when it computes the synchronization flag bit. The following describes the Proposal/Agreement mechanism in enhanced mode:

  • 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.

• Common mode: The current interface ignores the root port when it computes the synchronization flag bit. The following describes the Proposal/Agreement mechanism in common mode:

  • 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.