processEcnFeedback method

void processEcnFeedback(
  1. int ect0,
  2. int ect1,
  3. int ce
)

Processes ECN (Explicit Congestion Notification) feedback from ACK frames.

ECN allows routers to signal congestion before packet loss occurs, enabling more responsive congestion control. This is a placeholder for future OS-level ECN integration.

Per RFC 9000 Section 13.4:

  • ECT(0), ECT(1): ECN Capable Transport markings
  • CE: Congestion Experienced marking

An increase in CE count indicates congestion, which should trigger congestion response similar to packet loss.

Implementation

void processEcnFeedback(int ect0, int ect1, int ce) {
  // TODO: Implement ECN-based congestion control once OS integration is available
  // For now, this is a no-op placeholder
  //
  // When implemented, logic should:
  // 1. Track previous CE count
  // 2. If CE count increases, treat as congestion signal
  // 3. Enter recovery and reduce cwnd similar to packet loss
  // 4. Update metrics/logging
}