SDN Link Aggregation via LACP Mediation

The patent introduces an SDN controller as an intermediary that centralizes the link aggregation control function. The controller receives LACP packets from both SDN edge devices and traditional network devices, performs unified port selection and aggregation group management, and coordinates the negotiation process. This mediator approach resolves the protocol compatibility issue by providing a single point of control that can translate and manage LACP negotiations between devices with different capabilities, thereby improving reliability while managing complexity centrally rather than distributing it across multiple devices.

The patent extracts the dynamic port selection logic from individual network devices and concentrates it in the SDN controller. The controller independently analyzes LACP packets, evaluates port status and traffic requirements, and dynamically selects optimal ports for aggregation groups. By taking out this complex decision-making function from distributed devices and centralizing it in the controller, the system achieves high adaptability to changing network conditions while reducing control complexity at the edge devices, as they only need to participate in the standardized LACP negotiation process.

The patent implements preliminary action by having the SDN controller proactively send LACP packets to initiate and manage the aggregation negotiation process before actual data traffic requires the aggregated links. The controller pre-establishes aggregation groups, performs port selection in advance, and configures the forwarding rules beforehand. This preliminary setup ensures that when data traffic needs to flow through the aggregated links, the negotiation and configuration are already complete, thereby improving establishment reliability while minimizing the time impact on actual data transmission.