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<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi,<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span style='mso-spacerun:yes'>&nbsp;&nbsp;&nbsp;&nbsp;
</span>I am trying to integrate asterisk with <span class=SpellE>openser</span>
for a simple call. I am facing some issues with Asterisk. Below is the
explanation:<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span
style='mso-spacerun:yes'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; </span>I have a UA1
sending invite to UA2 through <span class=SpellE>Openser</span> and Asterisk
with the below sequence.<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span style='mso-spacerun:yes'>&nbsp;&nbsp;&nbsp;&nbsp;
</span>Sequence is UA1-&gt;<span class=SpellE>OpenSER</span>-&gt;Asterisk-&gt;<span
class=SpellE>Openser</span>-&gt;UA2<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><span style='mso-spacerun:yes'>&nbsp;&nbsp;&nbsp; </span><span
style='mso-spacerun:yes'>&nbsp;&nbsp;</span>When Asterisk gets the INVITE, the
INVITE contains two <span class=GramE>Via</span> headers, one of the UA1 and
the other <span class=SpellE>Openser&#8217;s</span>. <span class=GramE>As
Asterisk acts as a B2BUA, it <span class=SpellE>recreats</span> the Dialog.</span>
<span
style='mso-spacerun:yes'>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</span>So
before forwarding the INVITE to <span class=SpellE>Openser</span> back, it is
removing the <span class=GramE>Via</span> header of UA1 and also it is not
adding its own Via header. So when the INVITE reaches UA2 from <span
class=SpellE>Openser</span>, the INVITE will have only one <span class=GramE>Via</span>
header (which is of <span class=SpellE>Openser</span>). So when UA2 responds
with 180 Ringing, it will reach <span class=SpellE>Openser</span>, but <span
class=SpellE>Openser</span> cannot forward to Asterisk because it does not
contain the <span class=GramE>Via</span> header of Asterisk.<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Please help me out.<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Cheers,<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>-Sandeep A<o:p></o:p></span></font></p>

<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'><o:p>&nbsp;</o:p></span></font></p>

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