[OpenSIPS-Users] PRACK interworking requirements

[Antonios Psaras]

Hello Team

 

In most cases PRACK is needed for early audio services like Malicious Call Announcement. In those case the presence of 100rel and UPDATE is required. As this is a very well known issue and has already been implemented to few SBC Vendors, I suggest to check the documentation of such feature and implement something similar.

 

Here are two links for  <https://docs.oracle.com/en/industries/communications/session-border-controller/9.1.0/configuration/sip-prack-interworking.html#GUID-DF953FC6-35D0-4C8B-8812-3D7E72F7795E> PRACK Interworking and  <https://docs.oracle.com/en/industries/communications/session-border-controller/9.1.0/configuration/update-interworking.html#GUID-17824ABA-36FE-4E50-A6EB-F3BADEA9767E> UPDATE Interworking

 

As these features are prerequisite for a project we are involved, we are willing to contribute in any way to speed up the process.

 

Regards

 

Antonis Psaras

 

From: Users <users-bounces at lists.opensips.org> On Behalf Of Giovanni Maruzzelli
Sent: Τρίτη, 25 Νοεμβρίου 2025 13:14
To: Bogdan-Andrei Iancu <bogdan at opensips.org>
Cc: Giovanni Maruzzelli <gmaruzz at opentelecom.it>; OpenSIPS users mailling list <users at lists.opensips.org>
Subject: Re: [OpenSIPS-Users] PRACK interworking requirements

 

 

On Tue, Nov 25, 2025, 11:57 Bogdan-Andrei Iancu <bogdan at opensips.org <mailto:bogdan at opensips.org> > wrote:


The result here should be a dlg dedicated function to generate a PRACK from the onreply_route, like "dlg_answer_with_prack()" kind of function? or should we look into a more automatic approach, like flagging the dialog at creation to automatically generate the PRACK upon replies flagged with so?

 

personally I'm a control freak and would like better an explicit function, maybe even with parameters to modify things if needed :))

 

-giovanni

 

 

 

 

 


Regards,



Bogdan-Andrei Iancu
 
OpenSIPS Founder and Developer
  https://www.opensips-solutions.com
  https://www.siphub.com

On 25.11.2025 11:46, Giovanni Maruzzelli wrote:

hello OpenSIPSers,

 

in previous mails has been noticed that various ITSPs are starting to require PRACK support.

 

We know that PRACK belongs to endpoints, specifically phones and B2BUAs.

 

But...

 

There can be a use case where OpenSIPS will work as SBC (not necessarily using the b2b module)

 

So, we can have a case where we would like to support that the dialogue module insert the 100rel in the Supported: INVITE's header, and manage to send a PRACK method to acknowledge provisional responses

 

If and when 100rel/PRACK are "generated" by OpenSIPS, they will be filtered out (not propagated) to/from the endpoints, even if the endpoint would like to support it

 

Reference RFC: https://www.ietf.org/rfc/rfc3262.txt

 

I believe this will be enough to make ITSPs happy.

 

Further developments can be moved to future.

 

Would be very very nice to have this feature backported to OpenSIPS 3.6, being it the last of the 3.X series, and an LTS

 

Please let's gather here your thoughts , requests, corrections and observations on this issue.

 

Have a nice Monday you all!

 

-giovanni

 

-- 

Sincerely,

Giovanni Maruzzelli
OpenTelecom.IT
cell: +39 347 266 56 18

 

_______________________________________________
Users mailing list
Users at lists.opensips.org <mailto:Users at lists.opensips.org> 
http://lists.opensips.org/cgi-bin/mailman/listinfo/users

 

-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opensips.org/pipermail/users/attachments/20251125/18603f9e/attachment.html>