Dynamic Credit Control Circuit for Packet Switch Flow

The patent transitions from a static timer-based flow control mechanism to a dynamic credit-based mechanism. The ingress port continuously monitors credit values and adaptively transmits flow control packets only when credit thresholds are reached, making the system responsive to actual buffer conditions rather than following a fixed periodic schedule. This dynamic adaptation eliminates unnecessary packet transmissions while maintaining reliable credit starvation prevention.

The patent implements a feedback mechanism where the ingress port monitors its buffer credit values and uses this information to control flow control packet transmission. When credits are consumed and reach threshold values, the system generates flow control packets to notify the endpoint. This closed-loop feedback ensures packets are transmitted only when actually needed, preventing both credit starvation and unnecessary bandwidth consumption.

The patent replaces the static timer-based approach with a dynamic credit monitoring mechanism that automatically adapts to varying packet conditions. The system tracks actual credit consumption based on transmitted packet sizes and rates, adjusting flow control packet generation accordingly. While the implementation complexity increases slightly, the system gains significant adaptability to handle diverse packet workloads efficiently.

The ingress port performs self-monitoring of its buffer credit status and autonomously determines when flow control packets are needed. The system uses its own operational data (credit consumption patterns) to trigger transmissions, eliminating the need for external timing control or complex configuration. This self-service approach provides natural adaptation to varying transmission conditions while maintaining operational simplicity.