Bidirectional Forwarding Detection on Aggregated Links

The patent segments the aggregated link detection into multiple independent BFD sessions, each monitoring a specific physical port within the aggregated link. Instead of using a single BFD session that cannot accurately reflect the status of individual ports, the system creates multiple sessions (e.g., one per port) so that each session independently monitors its designated port's health, thereby improving detection precision without requiring complex coordination between sessions

The patent introduces a new dimension to BFD session management by establishing sessions at both the aggregated port level and the individual physical port level. This multi-level session structure allows the system to detect link status from multiple perspectives simultaneously, resolving the contradiction between simplicity and accuracy by adding structural dimensionality rather than increasing session count linearly

The patent merges the detection results of multiple individual port-level BFD sessions at the aggregated port level. By combining the status information from multiple sessions through logical operations (such as OR logic where the aggregated link is considered down only if all individual ports are down), the system achieves comprehensive monitoring without requiring each session to independently make the final determination, thereby managing complexity through consolidation

The patent creates a universal BFD session framework that can simultaneously serve multiple functions: individual port monitoring, aggregated link status determination, and fault isolation. Each BFD session is designed to be multi-functional, participating in both granular port-level detection and overall link health assessment, reducing the need for separate detection mechanisms and thereby managing complexity through functional consolidation