For Reference: https://support.software.dell.com/kb/sw6076
This guide explains the steps required to configure Quality of Service on SonicWall firewalls with the Enhanced firmware.
Note: It is recommended that you run the most current stable version of firmware.
You will need access to the firewall's web interface as well as know the upload and download speeds of your Internet connection.
Let's get started!
First log into the SonicWall and navigate to the Firewall Settings section in the left sidebar. Click on BWM (Bandwidth Management).
Set this to WAN and click Accept.
Now navigate to the Network section in the left sidebar and open the Interfaces. Click on the Configure button for the WAN interface. Proceed to the Advanced tab. Enable the Egress and Ingress Bandwidth Management. Set the Egress (upload) speed in Kbps. Set the Ingress (download) speed in Kbps. 1 Mbps = 1024 Kbps
*If you don't know what these speeds are you can run a speedtest at with http://speedtest.mytelepath.com or http://www.speedtest.net
*Run a couple tests to get a good average. Never round up as this will cause the QoS not to work properly.
Now we need to setup a firewall rule to which we will apply the QoS policy. First create an Address Object under the Network section in the WAN zone for sipbx.mytelepath.com. Second go to the Firewall section in the left sidebar and create a new rule for LAN to WAN with a destination of our Address Object that we just created for sipbx.mytelepath.com. Don't close this window, we're not done quite yet.
Now click on the Ethernet BWM tab of the new rule that we're about to create. Check the box to Enable Outbound Bandwidth Management.
Set the Guaranteed Bandwidth to the appropriate percentage or to a specific bandwidth number. As a rule of thumb each call uses ~100 kbps of bi-directional bandwidth. Multiply the number of concurrent calls (calls at the same time) by 100 to get the approximate bandwidth you'll need to maintain high quality calls.
Hit save and you are all set. The SonicWall will now prioritize the outbound voice traffic above other types of Internet traffic.
