Creating the router object that will apply constraints for VoIP traffic

In the example described in this document, TCP port 5060, corresponding to the SIP protocol, is used.
The availability and performance of each link are therefore tested by initiating a connection to the remote VoIP server from the firewall by using TCP port 5060.

In Configuration > Objects > Network objects:

  1. Click on Add.

    This opens a window to create and edit objects.
  2. In the menu on the left, select Router.

General properties

  1. Name the object (e.g., SD-WAN_VoIP).

Monitoring

  1. For the Detection method, select TCP Probe.
  2. For the Port, select sip_tcp.
  3. Adjust the Timeout (s) as needed.
  4. Adjust the Interval (s) of availability tests as needed.
  5. Adjust the ‎Failures before degradation (5 by default).

SD-WAN SLA (thresholds)

  1. Select SD-WAN SLA (thresholds).
  2. Adjust the Latency (ms) as needed.
  3. Adjust the Jitter (ms) as needed.
  4. Adjust the Packet loss rate (%) as needed.
  5. Do not enter an Unavailability rate (%).

Gateways

  1. In the Used gateways tab, click on Add.
  2. In the Gateway column, select the object Router1.
  3. In the Device(s) for testing availability column, select the remote VoIP server or group of remote VoIP servers (Remote_VoIP object in this technical note).
  4. Repeat steps 14 to 16 to add the object Router2.
  5. In the Backup gateways tab, click on Add.
  6. In the Gateway column, select the object Router3.
  7. In the Device(s) for testing availability column, select the remote VoIP server or group of remote VoIP servers (Remote_VoIP object in this technical note).

Advanced configuration

To maintain optimal link quality in as many cases as possible, the VoIP router object is configured with load balancing between the links used. Likewise, it is configured to use a backup link as soon as a main link is degraded or inaccessible.

  1. In Advanced configuration, select Load balancing By connection.
  2. For Enable backup gateways, selectWhen at least one gateway cannot be reached.
  3. Click on Apply then Save.