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<p>Hello,</p>
<p>with TCP there is no MTU. In the previous pcap you sent there was
a wrong Content-Length value. Was that fixed?</p>
<p>Cheers,<br>
Daniel<br>
</p>
<br>
<div class="moz-cite-prefix">On 06/02/2017 12:24, Hai Bui Duc Ha
wrote:<br>
</div>
<blockquote
cite="mid:CA+Gtc=Q_J2Ds=9FikZ5pK8zfezEdv=GpkR_3cseuz+fY94S7RQ@mail.gmail.com"
type="cite">
<div dir="ltr">Hi Daniel,
<div><br>
</div>
<div>I send you the pcap files on both client and server side.</div>
<div>Analyse this files, I see the packet can not "reassemble"
INVITE message at server side:</div>
<div>- At client.pcapng, it can detect 6 and 7th packets are
one.</div>
<div>- But on server.pcap, it can not "reassemble" 18 and 21st
packets.</div>
<div><br>
</div>
<div>I just explain as my understand. If you have any
information, please ask me.</div>
<div>I think the problem relate the MTU - fragmentation. But I'm
not sure about this.</div>
<div>Thank you for support !</div>
<div><br>
</div>
<div>Regards,</div>
<div>Hai Bui</div>
</div>
<div class="gmail_extra"><br>
<div class="gmail_quote">On Sun, Jan 22, 2017 at 4:33 PM, Hai
Bui Duc Ha <span dir="ltr"><<a moz-do-not-send="true"
href="mailto:hai.bui@htklabs.com" target="_blank">hai.bui@htklabs.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote" style="margin:0 0 0
.8ex;border-left:1px #ccc solid;padding-left:1ex">
<div dir="ltr">
<div>
<div>
<div>
<div>Hi <span class="m_4382236726686197603gmail-gI"></span><span
class="m_4382236726686197603gmail-gI"><span
name="Daniel-Constantin Mierla"
class="m_4382236726686197603gmail-gD">Daniel,<br>
<br>
</span></span></div>
<span class="m_4382236726686197603gmail-gI"><span
name="Daniel-Constantin Mierla"
class="m_4382236726686197603gmail-gD">Thank for
your advice.<br>
</span></span></div>
<span class="m_4382236726686197603gmail-gI"><span
name="Daniel-Constantin Mierla"
class="m_4382236726686197603gmail-gD">I will
capture and analyze the call log on both client
and kamailio to check the packet size.<br>
<br>
</span></span></div>
<span class="m_4382236726686197603gmail-gI"><span
name="Daniel-Constantin Mierla"
class="m_4382236726686197603gmail-gD">Regards,<br>
</span></span></div>
<span class="m_4382236726686197603gmail-gI"><span
name="Daniel-Constantin Mierla"
class="m_4382236726686197603gmail-gD">Hai Bui<br>
</span></span>
<div>
<div><span class="m_4382236726686197603gmail-gI"><span
name="Daniel-Constantin Mierla"
class="m_4382236726686197603gmail-gD"><br>
</span></span></div>
</div>
</div>
<div class="gmail_extra">
<div>
<div class="h5"><br>
<div class="gmail_quote">On Fri, Jan 20, 2017 at 3:38
PM, Daniel-Constantin Mierla <span dir="ltr"><<a
moz-do-not-send="true"
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 bgcolor="#FFFFFF" text="#000000"><span>
<p><br>
</p>
<br>
<div
class="m_4382236726686197603m_-3818873944372116824moz-cite-prefix">On
19/01/2017 22:56, Daniel-Constantin Mierla
wrote:<br>
</div>
<blockquote type="cite">
<p>Hello,<br>
</p>
<br>
<div
class="m_4382236726686197603m_-3818873944372116824moz-cite-prefix">On
19/01/2017 10:48, Hai Bui Duc Ha wrote:<br>
</div>
<blockquote type="cite">
<div dir="ltr">
<div>
<div>Hi Daniel,<br>
<br>
</div>
Thank you for reply.<br>
</div>
<br>
<div class="gmail_extra">
<div class="gmail_quote">On Tue, Jan
17, 2017 at 6:05 PM,
Daniel-Constantin Mierla <span
dir="ltr"><<a
moz-do-not-send="true"
href="mailto:miconda@gmail.com"
target="_blank">miconda@gmail.com</a>></span>
wrote:<br>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<p>Hello,</p>
<p>apparently I missed the
follow ups on this discussion,
dragged in by other topics on
mailing list. <br>
</p>
</div>
</blockquote>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<p>Can you get the pcap with all
the traffic taken on kamailio
server for the call (from
initial invite to the end of
the call)?</p>
</div>
</blockquote>
<div>I send you the pcap at enclosed
file. You can see the packet <b>No.5
</b>, it missing SIP message body:<br>
<i><b> Media Attribute
(a): rtpmap:8 PCMA/8000</b></i>
<div><i><b> Media
Attribute (a): rtpmap:101
telephone-event/8000</b></i></div>
<div><i><b> Media
Attribute (a): fmtp:101 0-16</b></i></div>
</div>
<blockquote class="gmail_quote"
style="margin:0px 0px 0px
0.8ex;border-left:1px solid
rgb(204,204,204);padding-left:1ex">
<div bgcolor="#FFFFFF">
<p> I expect that content length
is mismatching or there is a
'\0' inside the sdp.</p>
</div>
</blockquote>
<div>Can you explain me more about
this ? <br>
</div>
</div>
</div>
</div>
</blockquote>
TCP is a stream protocol, meaning that the
application (kamailio) need to read and
parse to figure out the end of a SIP
message. The state machine as per RFC
requires the application to read and
identify the Content-Length header, take its
value, read until the end of headers is
found (an empty line) and from there on read
as much as the value of Content-Length to
get the body and consider the end of message
there.<br>
<br>
If the sending application puts a lower
value in the Content-Length than the number
of chars in the body, the rest remains in
the buffer and the receiving application
(kamailio) attempts to parse a new SIP
message.<br>
<br>
The other thing I was thinking of was the
presence of '\0' which marks the end of
string in C.<br>
<br>
I will look at the pcap very soon and see
what I find there.<br>
<br>
</blockquote>
</span> The problem is the value of
Content-Lenght set by the client -- it is set
only to the size that it is view as part of the
invite. A bit later the client sends more sdp,
but exceeding the size sent in C-L header. That
part of SDP remains as garbage.<br>
<br>
So there is a bug in client app.<span><br>
<br>
Cheers,<br>
Daniel<br>
<pre class="m_4382236726686197603m_-3818873944372116824moz-signature" cols="72">--
Daniel-Constantin Mierla
<a moz-do-not-send="true" class="m_4382236726686197603m_-3818873944372116824moz-txt-link-abbreviated" href="http://www.twitter.com/miconda" target="_blank">www.twitter.com/miconda</a> -- <a moz-do-not-send="true" class="m_4382236726686197603m_-3818873944372116824moz-txt-link-abbreviated" href="http://www.linkedin.com/in/miconda" target="_blank">www.linkedin.com/in/miconda</a>
Kamailio World Conference - May 8-10, 2017 - <a moz-do-not-send="true" class="m_4382236726686197603m_-3818873944372116824moz-txt-link-abbreviated" href="http://www.kamailioworld.com" target="_blank">www.kamailioworld.com</a></pre>
</span></div>
</blockquote>
</div>
<br>
<br clear="all">
<br>
</div>
</div>
<span class="">-- <br>
<div class="m_4382236726686197603gmail_signature"
data-smartmail="gmail_signature">
<div dir="ltr">
<div>
<div dir="ltr">
<div>
<div dir="ltr">
<div>Hai Bui<br>
</div>
<div>VoIP engineer, Cvoice team, HTK-HCM
Office<br>
</div>
<div>
<div dir="ltr"><span><font color="#888888">
<div>
<font color="#000066">Mobile:
+84-165-618-9876<br>
</font></div>
</font></span></div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</span></div>
</blockquote>
</div>
<br>
<br clear="all">
<div><br>
</div>
-- <br>
<div class="gmail_signature" data-smartmail="gmail_signature">
<div dir="ltr">
<div>
<div dir="ltr">
<div>
<div dir="ltr">
<div>Hai Bui<br>
</div>
<div>VoIP engineer, Cvoice team, HTK-HCM Office<br>
</div>
<div>
<div dir="ltr"><span><font color="#888888">
<div>
<font color="#000066">Mobile:
+84-165-618-9876<br>
</font></div>
</font></span></div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</blockquote>
<br>
<pre class="moz-signature" cols="72">--
Daniel-Constantin Mierla
<a class="moz-txt-link-abbreviated" href="http://www.twitter.com/miconda">www.twitter.com/miconda</a> -- <a class="moz-txt-link-abbreviated" href="http://www.linkedin.com/in/miconda">www.linkedin.com/in/miconda</a>
Kamailio Advanced Training - Mar 6-8 (Europe) and Mar 20-22 (USA) - <a class="moz-txt-link-abbreviated" href="http://www.asipto.com">www.asipto.com</a>
Kamailio World Conference - May 8-10, 2017 - <a class="moz-txt-link-abbreviated" href="http://www.kamailioworld.com">www.kamailioworld.com</a></pre>
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