[SR-Users] Suggestion on receiving AAR

[Alberto Diez]

Hi Jyoti,

I give you in this email a hint of what you can try and most probably it 
works but I can't be 100% sure. The reason for this is I haven't been 
involved in the current implementation of the Kamailio P-CSCF Rx interface.

That Rx AAR which happens during registration is called in the standards 
"subscription to notification of IMS signaling path status", 
"subscription to notification of Change of IP-CAN Type", "Provisioning 
of SIP signaling flow information" and "subscription to notification of 
change of PLMN id" they are all optional features.  There doesn't seem 
to be a straightforward way to deactivate them in the current Kamailio 
P-CSCF (would be easy to implement a parameter for that) so I am going 
to suggest you the hard way and I expect that there is no dependency 
later when the other Rx functions are called (when Provisioning of 
Session Information during the INVITE etc.).  There shouldn't be any 
consequence of doing this that I suggest here, but I don't know in the 
current implementation, it probably takes less time if you try it out 
and see if there is any problem.

In the config file that has the routing logic of the REGISTER just 
comment out the logic associated with the Rx interface. If you are using 
the default one like in 
https://github.com/kamailio/kamailio/blob/master/misc/examples/ims/pcscf/route/register.cfg 
its the lines 27 until 65. You see that there is a ifdef WITH_RX there 
but you want to have WITH_RX set because later in the processing of the 
INVITE is this same define the one that controls the provisioning of 
session information to the PCRF.

An interesting note if there is any mantainer of these features, the AAR 
creates a session in the PCRF, if the AAR is sent when receiving the 
REGISTER instead of when receiving the 200 OK to the REGISTER, the 
session needs to be removed (by sending an STR) if the REGISTER is not 
successful. There is no such logic in the current Kamailio P-CSCF.  In 
TS 29213 Annex B.1 3GPP shows some of these flows (subscription to 
notification to signaling path status, provisioning of signaling flow 
information) ocurring when receiving a 200 OK to a REGISTER instead of 
when receiving the REGISTER itself. That would be in my opinion more 
appropriate (generates less signaling), although 3GPP does depict 
subscription to notiifcation of IP-CAN change and subscription to 
notification of PLMN id change as happening upon receipt of REGISTER 
instead of the 200 OK. That seems to me just 3GPP trying to make 
everyone crazy

Best regards

alberto

El 10/01/2022 a las 17:15, Jyoti Bansal escribió:
> Hello all,
> We are trying to connect kamailio ims to a pcrf,
> connection is successful. Whenever we register through bhoghe client , 
> we receive AAR on pcrf from kamailio ims(pcscf), so just need a 
> suggestion can we disable that till we receive invite from the soft phone?
> Can anyone help on this?
>
>
>
> Thanks,
> Jyoti bansal
>
> Confidentiality Notice and Disclaimer: This email (including any 
> attachments) contains information that may be confidential, privileged 
> and/or copyrighted. If you are not the intended recipient, please 
> notify the sender immediately and destroy this email. Any unauthorized 
> use of the contents of this email in any manner whatsoever, is 
> strictly prohibited. If improper activity is suspected, all available 
> information may be used by the sender for possible disciplinary 
> action, prosecution, civil claim or any remedy or lawful purpose. 
> Email transmission cannot be guaranteed to be secure or error-free, as 
> information could be intercepted, lost, arrive late, or contain 
> viruses. The sender is not liable whatsoever for damage resulting from 
> the opening of this message and/or the use of the information 
> contained in this message and/or attachments. Expressions in this 
> email cannot be treated as opined by the sender company management – 
> they are solely expressed by the sender unless authorized.
>
> __________________________________________________________
> Kamailio - Users Mailing List - Non Commercial Discussions
>    *sr-users at lists.kamailio.org
> Important: keep the mailing list in the recipients, do not reply only to the sender!
> Edit mailing list options or unsubscribe:
>    *https://lists.kamailio.org/cgi-bin/mailman/listinfo/sr-users
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.kamailio.org/pipermail/sr-users/attachments/20220110/2ab80475/attachment.htm>