Consistent NAT

1. Click on VoIP
2. Click on Settings
3. Set Enable consistent NAT to enabled
4. Every other checkbox on this page should be unchecked as well.
   
5. Click Accept
6. Click on Firewall Settings
7. Click on Advanced
8. Set Enable Stealth Mode and Randomize IP ID to disabled.
   
9. Click Accept
10. Under Network > Services click Add...
11. Fill the popup as follows:
    • Name: VoIP RTP
    • Protocol: UDP
    • Port Range: 3000 - 65000
    • Sub Type: None
12. Click Add
    
13. Click on Service Groups > Add Group...
14. Name: VOIP Services
15. Add the following services to the right box
    1. SIP
    2. VoIP RTP
16. Click Add
    
17. Navigate to Firewall > Access Rules
18. Click on Matrix
19. Click on the arrow under LAN > WAN
20. Click on Add...
    • Source Port: Any
    • Service: VOIP Services
    • Source: Any
    • Destination: Any 
    • Users Included: All
    • Users Excluded: None
    • Schedule: Always On
    • Comment: QoS for VoIP Phones
    • Enable Logging: True
    • Allow Fragmented Packets: True
      
21.  Click on the Advanced tab
    • UDP Connection Inactivity Timeout (seconds): 90
      
22. Click Firewall > Address Objects > Add
23. Fill out the following: 
    • Name: Name of the Assignment 
    • Zone Assignment: WAN
    • Type: Host
    • IP Address: IP of the Server
      NOTE: Find IP Addresses and Ports here
24. Add each IP Address for Voice Services as an Address Object
    
25. Create an Address Groupand add the address objects that were created
    • Name: Voice Services
26. Click Security Services 
27. Check each Service and see if it is enabled
28. If so, you need to enable the Exclusion List on each service and set it to Voice Services
29. Example: Content Filter
    
30. Once you exclude it, click Accept