ATA behind NAT router


When SIP is designed NAT is considered it is designed in public IP concept and it's not scope of SIP to work with NAT.  Fortunately there are already ways in the field deployment to workaround NAT.  Below is an example to typical NAT setup with ATA. There are three common solution to this NAT issue.

1. The NAT router to support SIP pass-though (This requires the router vendor to support it)

2. The ITSP deploy outbound proxy like Jasomi to auto-detect the public IP of the SIP client and act as proxy gateway between the two SIP client.

3. The ITSP deploy STUN server and SIP client also need to support STUN client.  By using STUN the client will first send STUN initiation packet to STUN server.  STUN server than tells the STUN client which IP it sees from the received initiation packet.  Than the client uses this IP to register to the proxy server and Prestige support STUN client.

 

Prestige behind NAT router example


 STUN client setting


 

To configure the STUN client setting please follow the below step.

Step 1. Open the web browser from your workstation to connect to the Prestige by entering the Management IP address of the Prestige.  The default management IP of Prestige is 192.168.5.1. 

Note: Make sure your the management host is in the same subnet as the Prestige management IP.

Step 2. Enter the administrator password appear on the page of login and click on login. The default is '1234'

Step 3. On the left column click on VoIP to enter phone port configuration page than close to end of the page under Advance Settings category click on the setting button to enter the advance setup page.

Step 4. Scroll down on the advance setup page until you see a category call STUN. 

Step 5. Check the check Active box to activate STUN client and fill in the STUN server address your ITSP provide you and the STUN server port.

Step 6. When you are done Click on Apply to save the setting and take effect.


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