Problem of matching the replies with the on-going transaction in OpenSER

Problem of matching the replies with the on-going transaction in OpenSER

Christian Lathion

Emin Gabrielyan

2007-06-15

We are facing a serious problem of matching the replies with the corresponding on-going transactions. We are using OpenSER v1.2.0 running on Debian Linux. The server is listening on two interfaces 212.249.15.4 and 195.129.125.74 [cfg].

The flow graph demonstrates the problem with an INVITE which arrives to the server from 128.179.67.35 IP address. The INVITE is retransmitted to the destination (62.189.34.7). The OpenSER server does not understand the 100-trying replies of the next hop (62.189.34.7) and retransmits the replies back to the originating IP 128.179.67.35. Since the 100-trying replies were not matched, OpenSER retransmits the INVITEs to the destination several times. As you can see the INVITEs are retransmitted even after the call is actually answered and the conversation is started.

[png], [pdf], [txt], [ps]

The contents of the SIP messages are in the text file [txt] and the PDF file [pdf]. Each page of the PDF file represents one SIP message.

The replies are left unmatched systematically. The rate of unmatched replies is very high. In average only 25% of replies are matched!

openser2:~/configs/unmatched-replies#

openser2:~/configs/unmatched-replies# expr `grep " ReplTr\. " /var/log/ser.log | wc -l`00 / `grep " Repl[ST][Lr]\. " /var/log/ser.log | wc -l`

openser2:~/configs/unmatched-replies#

[txt]

You may wish to look at the log file [log] of the server [cfg].

References:

http://switzernet.com/people/emin-gabrielyan/070524-openser-invite-100-handling/

http://www.voipuser.org/forum_topic_9749.html

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