Chapter 22 VoIP Solutions: SIP : FortiGate VoIP solutions: SIP : How the SIP ALG performs NAT : SIP NAT configuration example: source address translation (source NAT) : General configuration steps
  
General configuration steps
The following general configuration steps are required for this SIP configuration. This example uses the default VoIP profile. The example also includes security policies that specifically allow SIP sessions using UDP port 5060 from Phone A to Phone B and from Phone B to Phone A. In most cases you would have more than two phones so would use more general security policies. Also, you can set the firewall service to ANY to allow traffic other than SIP on UDP port 5060.
1. Add firewall addresses for Phone A and Phone B.
2. Add a security policy that accepts SIP sessions initiated by Phone A and includes the default VoIP profile.
3. Add a security policy that accepts SIP sessions initiated by Phone B and includes the default VoIP profile.