<html><head><style type='text/css'>p { margin: 0; }</style></head><body><div style='font-family: times new roman,new york,times,serif; font-size: 12pt; color: #000000'><div>Hi Bogdan,</div><div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8"><br></div><div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8">thanks for the tip, it works like a treat !</div><div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8"><br></div><div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8">Kind regards,</div><div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8">Giuseppe</div><div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8"><br></div><hr id="zwchr"><blockquote style="border-left:2px solid #1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><b>Da: </b>"Bogdan-Andrei Iancu" &lt;bogdan@opensips.org&gt;<br><b>A: </b>"Giuseppe Cardone" &lt;g.cardone@unidata.it&gt;, users@lists.opensips.org<br><b>Inviato: </b>Martedì, 15 luglio 2014 13:58:20<br><b>Oggetto: </b>Re: [OpenSIPS-Users] Fwd: PRACK Interworking with OpenSIPs<br><br>
  
    
  
  
    <div class="moz-cite-prefix"><tt>Hi Giuseppe,<br>
        <br>
        As proxy, it is a hard job to generate the PRACK requests. But
        the OpenSIPS B2B can do that - try to use the simples (the
        "topology-hiding") scenario and OpenSIPS b2b will automatically
        generate the PRACKs if "Require 100rel" is found in replies.<br>
        <br>
        Regards, <br>
      </tt>
      <pre class="moz-signature">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a class="moz-txt-link-freetext" href="http://www.opensips-solutions.com" target="_blank">http://www.opensips-solutions.com</a></pre>
      On 15.07.2014 12:50, Giuseppe Cardone wrote:<br>
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    <blockquote cite="mid:529027396.1029390.1405417802190.JavaMail.root@unidata.it">
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      <div style="font-family: times new roman,new york,times,serif;
        font-size: 12pt; color: #000000">Hi Bogdan,
        <div><br>
        </div>
        <div>Thank you for taking time to look at this issue.</div>
        <div><br>
        </div>
        <div>Your assumptions are all correct. &nbsp;However, there are
          cases, such as interconnect between operators, where PRACK is
          expected to be enforced on the interconnect for all calls
          (this is the case for example of the interconnects with
          Telecom Italia), ie outgoing INVITEs must always present the
          header Supported: 100rel.</div>
        <div><br>
        </div>
        <div>In our case, our voip network and certain clients don't
          support PRACK.</div>
        <div><br>
        </div>
        <div>This is why I am trying to see if with OpenSIPs I can
          implement "PRACK interworking", similarly to what commercial
          SBCs do.</div>
        <div><br>
        </div>
        <div>Do you have any suggestions as to if and how I may achieve
          this with OpenSIPs ? My understanding as far as I can see is
          that currently this is not possible.</div>
        <div><br>
        </div>
        <div>If so, just as a suggestion, you may want to consider
          features whereby the b2bua module is expanded to allow Actions
          such as the sending of additional SIP Requests such as PRACK
          and others, so that SBC functionality may be implemented.</div>
        <div><br>
        </div>
        <div>Thanks again for your attention and the hard work you put
          into OpenSIPs :-)</div>
        <div><br>
        </div>
        <div>Kind regards,</div>
        <div>Giuseppe</div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div><br>
        </div>
        <div><br>
          <br>
          <div><span></span></div>
          <hr id="zwchr">
          <blockquote style="border-left:2px solid
#1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><b>Da:
            </b>"Bogdan-Andrei Iancu" <a class="moz-txt-link-rfc2396E" href="mailto:bogdan@opensips.org" target="_blank">&lt;bogdan@opensips.org&gt;</a><br>
            <b>A: </b>"OpenSIPS users mailling list"
            <a class="moz-txt-link-rfc2396E" href="mailto:users@lists.opensips.org" target="_blank">&lt;users@lists.opensips.org&gt;</a>, "g cardone"
            <a class="moz-txt-link-rfc2396E" href="mailto:g.cardone@unidata.it" target="_blank">&lt;g.cardone@unidata.it&gt;</a><br>
            <b>Inviato: </b>Martedì, 15 luglio 2014 11:02:10<br>
            <b>Oggetto: </b>Re: [OpenSIPS-Users] Fwd: PRACK
            Interworking with OpenSIPs<br>
            <br>
            <div class="moz-cite-prefix"><tt>Hi Giuseppe,<br>
                <br>
                Before trying to fix it somewhere in the middle (in a
                proxy), let me say this PRACK negotiation must be
                negotiated between the end-point. If one of the end
                points does not support Prack, it should notify that. In
                your case, the callee (sending 180 + required 180) must
                not request PRACK if there was not such capability
                advertised by caller in INVITE (via the </tt><tt>Supported

                or Require header</tt><tt>). Please see <a class="moz-txt-link-freetext" href="http://www.ietf.org/rfc/rfc3262.txt" target="_blank">http://www.ietf.org/rfc/rfc3262.txt</a>
                page 4:<br>
                <br>
              </tt><br>
              <pre>   The rest of this discussion assumes that the initial request
   contained a Supported or Require header field listing 100rel, and
   that there is a provisional response to be sent reliably.</pre>
              <tt><br>
                So, the PRACK support must be advertised by caller in
                initial INVITE, otherwise the callee must not use it.
                Could you check in your traffic if this is the case? <br>
                <br>
                <br>
                Regards,<br>
              </tt>
              <pre class="moz-signature">Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
<a class="moz-txt-link-freetext" href="http://www.opensips-solutions.com" target="_blank">http://www.opensips-solutions.com</a></pre>
              On 14.07.2014 11:06, Giuseppe Cardone wrote:<br>
            </div>
            <blockquote cite="mid:175342498.765778.1405325170280.JavaMail.root@unidata.it">
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              <div style="font-family: times new roman,new
                york,times,serif; font-size: 12pt; color: #000000">
                <div>Hello,</div>
                <div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8"><br>
                </div>
                <div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8">does
                  anyone have any ideas regarding this issue ?</div>
                <div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8"><br>
                </div>
                <div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8">Many
                  thanks for any tips you may have.</div>
                <div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8"><br>
                </div>
                <div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8">Kind
                  regards,</div>
                <div id="956e4f19-49f6-4bbc-bdd4-c56101d702d8">Giuseppe</div>
                <hr id="zwchr">
                <blockquote style="border-left:2px solid
#1010FF;margin-left:5px;padding-left:5px;color:#000;font-weight:normal;font-style:normal;text-decoration:none;font-family:Helvetica,Arial,sans-serif;font-size:12pt;"><b>Da:

                  </b>"Giuseppe Cardone" <a class="moz-txt-link-rfc2396E" href="mailto:g.cardone@unidata.it" target="_blank">&lt;g.cardone@unidata.it&gt;</a><br>
                  <b>A: </b><a class="moz-txt-link-abbreviated" href="mailto:users@lists.opensips.org" target="_blank">users@lists.opensips.org</a><br>
                  <b>Inviato: </b>Giovedì, 10 luglio 2014 15:11:54<br>
                  <b>Oggetto: </b>PRACK Interworking with OpenSIPs<br>
                  <br>
                  <style>p { margin: 0; }</style>
                  <div style="font-family: times new roman,new
                    york,times,serif; font-size: 12pt; color: #000000">
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;">Hello,</div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;"><br>
                    </div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;">I am trying OpenSIPs and would like to
                      figure out if I can use it to perform sip
                      interworking between two UA's, one requiring PRACK
                      and another that doesn't support it.</div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;"><br>
                    </div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;">In essence when OpenSIPs receives a 18x
                      response with headers "Required: 100rel" and
                      "RSeq" from the called party, it should initiate a
                      PRACK request towards the called party itself,
                      but, as you might expect from a proxy, I don't see
                      any function to do this. &nbsp;However, maybe someone
                      with a better understanding of OpenSIPs can tell
                      me if it is available.</div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;"><br>
                    </div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;">The b2bua module is were I was placing my
                      hopes. &nbsp;However, here too I cannot see a way to
                      initiate a PRACK request, or any request apart
                      from an INVITE (using the 'bridge' action) or a
                      BYE (using the 'end_dialog_leg').</div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;"><br>
                    </div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;">Can anyone confirm whethere my conclusions
                      on PRACK interworking with OpenSIPs are correct
                      and/or provide any ideas as to how this may be
                      accomplished ?</div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;"><br>
                    </div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;">Many thanks,</div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;"><br>
                    </div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;">Giuseppe&nbsp;</div>
                    <div style="color: rgb(0, 0, 0); font-family: 'times
                      new roman', 'new york', times, serif; font-size:
                      12pt;"><br>
                    </div>
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              <pre>_______________________________________________
Users mailing list
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