<div dir="ltr"><br><div>Thanks for this answer. The voip provider is not really eager to alter its SBC as it considers that the contact field is not mandatory in the ACK. The RFC states (section 8.1.1.8)</div><div><br></div><div><pre class="gmail-newpage">The Contact header field MUST be present and contain exactly one SIP
or SIPS URI in any request that can result in the establishment of a
dialog. For the methods defined in this specification, that includes
only the INVITE request</pre><pre class="gmail-newpage"><br></pre>The ACK does not establish the dialog, no new call id / dialog id is being generated.</div><div><br></div><div>I guess I need to implement the mechanism you've described, unless you think they mis-interpret the RFC,</div><div><br></div><div>Regards</div><div>J.</div></div><div class="gmail_extra"><br><div class="gmail_quote">On Thu, Jan 4, 2018 at 4:48 AM, Daniel-Constantin Mierla <span dir="ltr"><<a href="mailto:miconda@gmail.com" target="_blank">miconda@gmail.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div text="#000000" bgcolor="#FFFFFF">
<p>Hello,</p>
<p>if one side of the call is breaking the contact, then a
workaround in kamailio is to use htable to store the contact
address per callid+from/to tag. I encountered couple of times such
situation and the condition in the config file is like:</p>
<p> - if the r-uri of ACK (BYE, etc...) matches "myself", then
check to see if there is a record in an htable corresponding to
callid and to-tag, if yes, use it</p>
<p>Contact for caller is set in htable as INVITE is received and for
callee when then 200ok is received.</p>
<p>If dialog module is used, then the contact from the dialog
structure can be used. With 5.1 or newer, dialog offers a
dedicated function for this:</p>
<p> -
<a class="m_7697486188975008417moz-txt-link-freetext" href="https://www.kamailio.org/docs/modules/stable/modules/dialog.html#dialog.f.dlg_set_ruri" target="_blank">https://www.kamailio.org/docs/<wbr>modules/stable/modules/dialog.<wbr>html#dialog.f.dlg_set_ruri</a></p>
<p>For older versions, the address has to be taken from $dlg(...)
variable, with some conditions to detect if it is the caller or
callee side.</p>
<p>Cheers,<br>
Daniel<br>
</p><div><div class="h5">
<br>
<div class="m_7697486188975008417moz-cite-prefix">On 03.01.18 16:16, Sebastian Damm
wrote:<br>
</div>
</div></div><blockquote type="cite"><div><div class="h5">
<div dir="ltr">Hi Jean,
<div><br>
</div>
<div>as pointed out earlier, the ACK is probably broken. Every
packet after the 200 OK should have the contact of the 200 OK
in the Request URI. Your example packet carries probably the
original request URI, which is most certainly wrong, exept if
you use some topology hiding.</div>
<div><br>
</div>
<div>This is something you can't fix but the voip provider has
to fix. They apparently can't handle proxied SIP connections.</div>
<div><br>
</div>
<div>Regards,</div>
<div>Sebastian</div>
<div class="gmail_extra"><br>
<div class="gmail_quote"><br>
</div>
</div>
</div>
<br>
<fieldset class="m_7697486188975008417mimeAttachmentHeader"></fieldset>
<br>
</div></div><span class=""><pre>______________________________<wbr>_________________
Kamailio (SER) - Users Mailing List
<a class="m_7697486188975008417moz-txt-link-abbreviated" href="mailto:sr-users@lists.kamailio.org" target="_blank">sr-users@lists.kamailio.org</a>
<a class="m_7697486188975008417moz-txt-link-freetext" href="https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users" target="_blank">https://lists.kamailio.org/<wbr>cgi-bin/mailman/listinfo/sr-<wbr>users</a>
</pre>
</span></blockquote><span class="">
<br>
<pre class="m_7697486188975008417moz-signature" cols="72">--
Daniel-Constantin Mierla
<a class="m_7697486188975008417moz-txt-link-abbreviated" href="http://www.twitter.com/miconda" target="_blank">www.twitter.com/miconda</a> -- <a class="m_7697486188975008417moz-txt-link-abbreviated" href="http://www.linkedin.com/in/miconda" target="_blank">www.linkedin.com/in/miconda</a>
Kamailio Advanced Training - <a class="m_7697486188975008417moz-txt-link-abbreviated" href="http://www.asipto.com" target="_blank">www.asipto.com</a>
Kamailio World Conference - May 14-16, 2018 - <a class="m_7697486188975008417moz-txt-link-abbreviated" href="http://www.kamailioworld.com" target="_blank">www.kamailioworld.com</a></pre>
</span></div>
<br>______________________________<wbr>_________________<br>
Kamailio (SER) - Users Mailing List<br>
<a href="mailto:sr-users@lists.kamailio.org">sr-users@lists.kamailio.org</a><br>
<a href="https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users" rel="noreferrer" target="_blank">https://lists.kamailio.org/<wbr>cgi-bin/mailman/listinfo/sr-<wbr>users</a><br>
<br></blockquote></div><br></div>