Configuring quality of service

Last Updated : Dec 04, 2024 |

About this task

Configure the quality of service parameters, including packet priority, jitter buffer, the size of Maximum Transmission Unit (MTU), network redundancy, and other settings. You can also enable RTP and TCP packet retransmission and traffic control. Quality of service eliminates data loss, reduces network latency and jitter, and provides an optimal audio and video experience for call and streaming participants.

Procedure

  1. On the Settings menu, go to Network > Service Quality.
  2. On the Service Quality page, for the Type Of Service setting, select one of the following options:

    • IP Priority: To determine the outbound port queue for IP packets based on the precedence bits in the packet header.

    • Differentiated Services: To determine the network traffic priority based on the differentiated services code point (DSCP) value in the packet header.

  3. For the Audio setting, select the audio traffic precedence value.
  4. For the Video setting, select the video traffic precedence value.
  5. For the Control setting, select the signaling traffic precedence value.
  6. For the Maximum Jitter Buffer setting, select the delay in milliseconds with which the jitter buffer sends the queued data packets to the recipient.

    By adjusting this setting, you can reduce the network jitter and ensure a smoother audio and video.

  7. For the Packet MTU setting, select the maximum size of data packets in bytes.

    This setting determines the largest packet size that you can send over the network.

  8. For the Maximum Transmission Unit(MTU) setting, select the maximum size of any data unit in bytes, including packets and frames.
  9. To enable Rapid Transfer Protocol (RTP) packet loss retransmission, select the Enable Media Optimization check box.
  10. If you enabled media optimization, for the Maximum delay of packet loss recovery setting, select the maximum delay for restoring lost data packets in milliseconds.
  11. For the Redundancy setting, select the level of redundancy to provide alternate paths for sending traffic in case of a network failure.
  12. To resend the lost RTP packets using Automatic Repeat Request (ARQ), select the Enable RTP Packet Loss Retransmission check box.
  13. To enable adaptive mode for the RTP connection data flow, select the Enable RTP Auto Adaptive Rate check box.

    If adaptive mode is enabled, the video resolution decreases during calls if the network bandwidth is low until it is restored.

  14. To resend RTP packets using Forward Error Correction (FEC), select the Enable Simple Retransmission check box.
  15. If you enabled simple retransmission, for the Redundancy Rate setting, select the level of redundancy for resending RTP packets.

    The level of redundancy corresponds to the number of times for resending packets. For example, if you select Small, the packets are sent only once, and if you select Large, the packets are resent three times.

  16. To resend only audio packets, select the Valid For Audio Only check box.
  17. To enable traffic control based on the network bandwidth and packet delivery feedback, select the Enable Traffic Control check box.
  18. If you enabled traffic control, for the Call Offset Rate setting, select the call rate value in kilobits per second.

    The Default Call Rate value that you set on the Call Options page includes both audio and video traffic. The audio traffic mostly remains static, but you can determine how the video bit rate can change depending on the network bandwidth by setting the Call Offset Rate value. With a higher Call Offset Rate value, you can achieve a higher video encoding bit rate.

  19. Click Save.