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DoS & spoof protection and VoIP

Condition

Unstable VoIP connection if DoS settings for UDP rate are applied.

Cause

UDP flood settings cause VoIP traffic to drop.

Remedy

  1. Go to Intrusion prevention > DoS & spoof protection.
  2. Under DoS settings, clear the Apply flag checkboxes for UDP flood.
  3. Test the VoIP connection.

  4. If this setting resolves the VoIP issue, lower the UDP flood protection values before applying the flag again.

    A single value doesn't work for all environments. Adjust the values until you find those that work best for your VoIP setup.