<html>
<head>
<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii">
<meta name=Generator content="Microsoft Word 10 (filtered)">
<style>
<!--
/* Style Definitions */
p.MsoNormal, li.MsoNormal, div.MsoNormal
{margin:0in;
margin-bottom:.0001pt;
font-size:12.0pt;
font-family:"Times New Roman";}
a:link, span.MsoHyperlink
{color:blue;
text-decoration:underline;}
a:visited, span.MsoHyperlinkFollowed
{color:purple;
text-decoration:underline;}
span.EmailStyle17
{font-family:Arial;
color:windowtext;}
@page Section1
{size:8.5in 11.0in;
margin:1.0in 1.25in 1.0in 1.25in;}
div.Section1
{page:Section1;}
-->
</style>
</head>
<body lang=EN-US link=blue vlink=purple>
<div class=Section1>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Hi Everyone,</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am using SER version </span></font></p>
<p class=MsoNormal style='text-indent:.5in'><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>Server: Sip EXpress router (0.9.2 (i386/linux)).</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>I am initiating a call from a caller </span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>sip</span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'> UA to a callee
</span></font><font size=2 face=Arial><span style='font-size:10.0pt;font-family:
Arial'>sip</span></font><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> UA and I am receiving the </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>ACK response to the INVITE from the callee on SER. Before loose_route
processing </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>it looks like this:</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>ACK </span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:2224440133@10.1.10.65:5060
SIP/2.0</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Via: SIP/2.0/UDP 172.16.15.52:5060;rport;branch=z9hG4bK83e54f590401584628d473053d1ef8a8</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>From: <</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:2224440132@xxx.yyy.zzz:5060>;tag=1cac2190</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>To: <</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:2224440131@xxx.yyy.zzz:5060>;tag=d323038ba423a329i0</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Call-ID: 66cb6ba85191e6025ebde2c552177442@172.16.15.52</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>CSeq: 1
ACK
</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Contact: <</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:2224440132@172.16.15.52:5060></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Max-Forwards: 70
</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Route: <</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:10.1.10.65;ftag=1cac2190;lr>,<</span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>sip</span></font><font
size=2 face=Arial><span style='font-size:10.0pt;font-family:Arial'>:10.1.10.65;ftag=1cac2190;lr></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Content-Length: 0
</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>
</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>
</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>After loose_route processing and relaying, the ACK, instead
of being routed to the callee</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>(2224440133) User Agent, it is received back at SER looking
like this:</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>ACK </span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:10.1.10.65;ftag=1cac2190;lr
SIP/2.0</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Record-Route: <</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:10.1.10.65;ftag=1cac2190;lr=on></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Via: SIP/2.0/UDP 10.1.10.65;branch=0</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Via: SIP/2.0/UDP 172.16.15.52:5060;rport=5060;branch=z9hG4bK83e54f590401584628d473053d1ef8a8</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>From: <</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:2224440132@xxx.yyy.zzz:5060>;tag=1cac2190</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>To: <</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:2224440131@xxx.yyy.zzz:5060>;tag=d323038ba423a329i0</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Call-ID: 66cb6ba85191e6025ebde2c552177442@172.16.15.52</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>CSeq: 1 ACK</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Contact: <</span></font><font size=2 face=Arial><span
style='font-size:10.0pt;font-family:Arial'>sip</span></font><font size=2
face=Arial><span style='font-size:10.0pt;font-family:Arial'>:2224440132@172.16.15.52:5060></span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Max-Forwards: 16</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Route:</span></font></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'>Content-Length: 0</span></font></p>
<p class=MsoNormal></p>
<p class=MsoNormal><font size=2 face=Arial><span style='font-size:10.0pt;
font-family:Arial'> </span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Why is SER routing this ACK request incorrectly?! </span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> </span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Is the syntax of the original ACK generated by the Callee’s UA
incorrect?!</span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> </span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>I would appreciate any help as I can’t figure it whether there is
something wrong</span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>with ACK’s syntax or there is a bug in SER’s loose_route
processing?!</span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> </span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>Thanks a lot</span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'> </span></font></p>
<p class=MsoNormal><font size=3 face="Times New Roman"><span style='font-size:
12.0pt'>ramin</span></font></p>
</div>
</body>
</html>