Hello,

indeed there is no guaranteed unique token per SIP packet.

If one wants to identify the transaction, need to look at Call-Id and CSeq, plus Via header (the via is relevant when there is a forking proxy upstream).

Regarding the checksum, the upd checksum is not available, but kamailio can also deal with tcp/tls/sctp. You can build md5 or shaX checksums in the configuration file using transformations, see:

  - http://www.kamailio.org/wiki/cookbooks/devel/transformations#smd5

For example: $(mb{s.md5}).

Cheers,
Daniel

On 19/05/15 07:55, Alex Balashov wrote:
‎Hello,

Various GUIDs and other signatures in SIP exist to link branches, transactions, and dialogs, but none that are uniquely generated per packet. The best you're going to be able to do is to compute a checksum, but even that is no guarantee in a REGISTER flow.

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Sent from my BlackBerry.
From: jay binks
Sent: Tuesday, May 19, 2015 00:47
To: Kamailio (SER) - Users Mailing List
Reply To: Kamailio (SER) - Users Mailing List
Subject: [SR-Users] SIP Packet identifier

So im logging lots of information to Syslog to assist our helpdesk in diagnosing customer issues.

Im seeing LOTS of user agents that re-use the sip Call-ID ( especially in registers ).
What im wanting to be able to do is link a log message ( that I log at some point in my dialplan ) to a specific SIP packet ( viewed from voipmonitor, HOMER, wireshark ).

I cant REALLY see anything in the SIP to uniquely identify a packet, however if kamailio provided the UDP packet checksum in a pseudo variable then we could combine that with the sip call-id to hopefully do what im after.

does anyone else have any ideas about how do what im after ?

--
Sincerely

Jay



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