***NOTE: This guide assumes standard registration with your trunk at SIP.US. This model of SonicWALL is incompatible with IP Based Authentication at SIP.US if you do not have a separate static IP for VoIP traffic and that configuration is not addressed in this guide***
Many of our customers use Dell SonicWALL products. These products provide some advanced security functionality by transforming ports in a randomized fashion. This can create some problems with SIP traffic if steps are not taken to assure the stability of port transformations.
An additional layer of complexity is added with Dell's 3.x firmware, as it is not capable of assigning static ports while maintaining NAT capabilities without additional static IP addresses. This brief guide will give you the settings you need to get your PBX working with SIP.US under most circumstances where you must share 1 public IP between standard internet and VoIP traffic.
1. After logging into your SonicWALL click on the "Firewall" tab.
2. Go to the "VOIP" folder
3. Check the boxes for "Enable consistent NAT" and "Enable Sip Transformations"
4. Click "Apply"
5. From the SIP.US portal, go to "Manage Your Sip Trunks / Numbers" or the "Sip Trunking" tab.
6. Your trunk should now say "Registered" and show your public IP address with a random port number
The SonicWALL will keep track of the ports it is transmitting to us, and we will respond back symmetrically to the port that is sent. When the sonic wall receives a transmission from SIP.US on the port it is registered on, it will automatically translate the IP and Port combination to the internal IP and Port of the SIP capable device that is registered with SIP.US. The SonicWALL will also open the necessary RTP ports based on the connection information received from SIP.US.
***DO NOT FORWARD ANY PORTS BASED ON GENERIC GUIDANCE FROM SIP.US! PORT FORWARDS ARE NOT NECESSARY WITH THESE SONIC WALL DEVICES!***