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    <tt>Hi Yuriy,<br>
      <br>
      As you are using Kamailio and FreeSWITCH, it is more appropriate
      to post the question to their mailing lists.<br>
      <br>
      Regards,<br>
    </tt>
    <pre class="moz-signature" cols="72">Bogdan-Andrei Iancu

OpenSIPS Founder and Developer
  <a class="moz-txt-link-freetext" href="https://www.opensips-solutions.com">https://www.opensips-solutions.com</a>

</pre>
    <div class="moz-cite-prefix">On 5/14/20 6:09 PM, Yuriy Nasida wrote:<br>
    </div>
    <blockquote type="cite"
cite="mid:CADihe3JjFEk-NJtYk6jj9_wjNYD=53V=TBa3SA1XDBnbF=kt+Q@mail.gmail.com">
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        <div>I use kamilio but I think it works in the same way for
          Opensips.</div>
        <div><br>
        </div>
        <div>Well, I saw similar questions in the list already but looks
          like nobody has answer.</div>
        <div><br>
        </div>
        <div>Please look at REFER below.</div>
        <div><br>
        </div>
        <div>Kamilio gets REFER from MS and sends it to FS node. Next,
          FS node try to make 3th call for some reason.I expect that FS
          will not do 3th call and just will connect Alice and Bob
          itself.<br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div>2020/05/14 12:32:00.637027 KAM_IP:5060 -> FS_IP:5060<br>
          REFER <a class="moz-txt-link-freetext" href="sip:Alice_number@FS_IP:5060;transport=udp">sip:Alice_number@FS_IP:5060;transport=udp</a> SIP/2.0<br>
          FROM:
Customer1<a class="moz-txt-link-rfc2396E" href="sip:MS_TRUNK_NUMBER@sip.pstnhub.microsoft.com:5061;user=phone"><sip:MS_TRUNK_NUMBER@sip.pstnhub.microsoft.com:5061;user=phone></a>;tag=a860c50a3fb54d08b4e5740fa2dfb3d6<br>
          TO:
          <a class="moz-txt-link-rfc2396E" href="sip:Alice_number@FQDN_OF_TRUNK:5061"><sip:Alice_number@FQDN_OF_TRUNK:5061></a>;user=phone;tag=e8ct9S6ty13va<br>
          CSEQ: 4 REFER<br>
          CALL-ID: 2c71b2a6669b5343a231e1244b19c945<br>
          MAX-FORWARDS: 50<br>
          Via: SIP/2.0/UDP
FQDN_OF_TRUNK:5060;branch=z9hG4bK10ae.2c42897feca117121a23bf0c8d54cd19.0;i=c<br>
          VIA: SIP/2.0/TLS 52.114.75.24:5061;branch=z9hG4bK7e3e8998<br>
          CONTACT:
<<a class="moz-txt-link-freetext" href="sip:api-du-a-euwe.pstnhub.microsoft.com:443;x-i=6b68e7aa-f5e2-44ec-9edf-0bacbabfce07;x-c=2c71b2a6669b5343a231e1244b19c945/d/8/b68f86794a8e44d19543f8edbee6b2fc">sip:api-du-a-euwe.pstnhub.microsoft.com:443;x-i=6b68e7aa-f5e2-44ec-9edf-0bacbabfce07;x-c=2c71b2a6669b5343a231e1244b19c945/d/8/b68f86794a8e44d19543f8edbee6b2fc</a><br>
          CONTENT-LENGTH: 0<br>
          REFER-TO:
<a class="moz-txt-link-rfc2396E" href="sip:Bob_number@sip.pstnhub.microsoft.com:5061;user=phone;transport=tls"><sip:Bob_number@sip.pstnhub.microsoft.com:5061;user=phone;transport=tls></a><br>
          REFERRED-BY:
<<a class="moz-txt-link-freetext" href="sip:sip.pstnhub.microsoft.com:5061;x-m=8:orgid:21bc47d3-c050-4292-8234-46f7005b97aa;x-t=fb788ef8-3c4c-455a-8d62-f3c20832c0d3;x-ti=6b68e7aa-f5e2-44ec-9edf">sip:sip.pstnhub.microsoft.com:5061;x-m=8:orgid:21bc47d3-c050-4292-8234-46f7005b97aa;x-t=fb788ef8-3c4c-455a-8d62-f3c20832c0d3;x-ti=6b68e7aa-f5e2-44ec-9edf</a>-<br>
acbabfce07;x-tt=aHR0cHM6Ly9hcGktZHUtYS1ldXdlLnBzdG5odWIubWljcm9zb2Z0LmNvbS92MS9uZ2MvY2FsbG5vdGlmaWNhdGlvbj9kY2k9YzIxMjE3MzEyNTQ2NDk1ZjlhYTcwODliYTkwNGIxZGQ%3D><br>
          USER-AGENT: Microsoft.PSTNHub.SIPProxy v.2020.5.6.2 i.EUWE.4<br>
          ALLOW: INVITE,ACK,OPTIONS,CANCEL,BYE,NOTIFY<br>
          P-ASSERTED-IDENTITY: <a class="moz-txt-link-rfc2396E" href="tel:MS_TRUNK_NUMBER"><tel:MS_TRUNK_NUMBER></a>,<<a
            href="mailto:sip%3Acustomer1@m365x587912.onmicrosoft.com"
            target="_blank" moz-do-not-send="true">sip:customer1@m365x587912.onmicrosoft.com</a>><br>
          PRIVACY: id<br>
          X-AUTH-IP: 52.114.75.24<br>
          X-AUTH-PORT: 3136<br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div>Any advice? </div>
      </div>
      <br>
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      <pre class="moz-quote-pre" wrap="">_______________________________________________
Users mailing list
<a class="moz-txt-link-abbreviated" href="mailto:Users@lists.opensips.org">Users@lists.opensips.org</a>
<a class="moz-txt-link-freetext" href="http://lists.opensips.org/cgi-bin/mailman/listinfo/users">http://lists.opensips.org/cgi-bin/mailman/listinfo/users</a>
</pre>
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