[Kamailio-Users] SIP-T: Multipart SDPs, ISUP parsing, etc

[Kristian Kielhofner]

Hello everyone,

  Feel free to set $OSSPROXY to whatever you like =
Kamailio/OpenSIPS/OpenSER (for those of you who can't let go).

  $OSSPROXY is my favorite SIP toolkit.  In addition to being an
excellent proxy and registrar it serves as a platform to do SIP
mangling and wrangling.  With that in mind let me propose a crazy
idea...

  How hard would it be to get $OSSPROXY to be able to parse what is
commonly referred to as SIP-T (RFC 3372)?  I understand $OSSPROXY has
no business getting too involved in the SDP but I feel it makes sense
in some instances (like this one).  What if I want to make a routing
decision based on an encapsulated ISUP parameter of some sort?  Who
knows what it could be!?!?  Maybe there are some other uses but that
makes the most sense and seems to be the most practical.  It should be
possible to develop an $OSSPROXY module to:

- Use the SDP parser to find the ISUP SDP part:

http://www.kamailio.net/dokuwiki/doku.php/development:sdp-parsing

- Pass that part into a "real" ISUP parser (if necessary).  I couldn't
seem to find the perfect library but perhaps something like this could
work:

http://www.openss7.org/isup.html

- Make the ISUP parameters available via AVPs, pseudo variables, etc
for use in the $OSSPROXY script.

  I don't really have a need for this but it seems like it could be
cool.  Am I nuts?

-- 
Kristian Kielhofner
http://blog.krisk.org