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    NAT for VOIP phone

    Scheduled Pinned Locked Moved NAT
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    • N
      nsumner
      last edited by

      I had a small problem with the NAT with my VOIP line. It establishes an outbound connection on port 5060 (standard SIP) to the SIP server. The SIP server sometimes communicates to it of course as well. The communcation from the SIP server was getting blocked by the firewall. Creating a NAT rule solved the problem but there really should be no need for the NAT rule. Is there any way to resolve this?

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      • H
        hoba
        last edited by

        SIP behind a NAT without portforwards only works if your SIP provider has a STUN server that helps to transverse the NAT. Search the forums for SIP related topics, there are already some solutions for this problem if you don't have a STUN server.

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        • R
          romst
          last edited by

          @nsumner:

          I had a small problem…

          You may use sip-proxy in packages, without forwarding any ports.
          Or, use IAX2-protocol.

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          • N
            nsumner
            last edited by

            I can't use a STUN server. A STUN server doesn't solve the problem and according to FWD a STUN server can not be used for a syymetrical NAT. They however suggest using a Outgoing Proxy. I will see if my Service provider has an outgoing proxy avaliable.

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            • T
              thinair
              last edited by

              I use a SIP here, I haven't configured a STUN server in the SIP, nor have I setup any port forwarding.  I pretty much just plugged it in and configured the sip.domain.com registration address with my user/pass and it just worked.

              Nelson Papel

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              • H
                hoba
                last edited by

                Then you have a good provider that is using a proxy at their end which will rewrite the sipmessages with what they see the packets coming from.

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                • JeGrJ
                  JeGr LAYER 8 Moderator
                  last edited by

                  As it may cover the topic, I had problems with my old router and VoIP (United Internet), too. Problem was outgoing conections on random ports. But with pfSense and static port option in NAT, the problem disappeard automagically. The only thing you need is the one NAT rule mentioned and thats it. No Problems here anymore. Without any other software as e.g. the already mentioned proxies, you'll have to use a NAT rule.

                  Grey

                  Don't forget to upvote 👍 those who kindly offered their time and brainpower to help you!

                  If you're interested, I'm available to discuss details of German-speaking paid support (for companies) if needed.

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