[SR-Users] t_relay dying ?

[Jean Cérien]

Many, many thanks !

I've posted the full dialog unredacted here: https://pastebin.com/EE9iwgZf

The OK from Kamailio back to VOIP provider has
Record-Route: <sip:KAMAILIOIP;lr=on;ftag=SD2rbta01-8dd0e72b-0016-0379-
0000-0000;did=e0c.e0a1>
Contact: <sip:NUMBER at ASTERISKIP:5060>

So my understanding is that the ACK should be
ACK sip:NUMBER at ASTERISKIP:5060 SIP/2.0
....
and not
ACK sip:NUMBER at KAMAILIOIP:5060 SIP/2.0

Am I understanding correctly ?

Rgds
J

On Mon, Jan 8, 2018 at 11:28 AM, Sebastian Damm <damm at sipgate.de> wrote:

> Hi,
>
> On Mon, Jan 8, 2018 at 2:39 PM, Jean Cérien <cerien.jean at gmail.com> wrote:
>
>>
>> Thanks for this answer. The voip provider is not really eager to alter
>> its SBC as it considers that the contact field is not mandatory in the ACK.
>> The RFC states (section 8.1.1.8)
>>
>
> The problem is not that the ACK doesn't carry a Contact header. The
> problem is that the ACK is constructed incorrectly. This is what the RfC
> says to UAC behavior (section 12.1.2):
>
> The route set MUST be set to the list of URIs in the Record-Route header
> field from the response, taken in reverse order and preserving all URI
> parameters. If no Record-Route header field is present in the response, the
> route set MUST be set to the empty set. This route set, even if empty,
> overrides any pre-existing route set for future requests in this dialog. *The
> remote target MUST be set to the URI from the Contact header field of the
> response.*
>
> This is what the carrier's SBC gets wrong. It doesn't address your
> Asterisk but instead addresses your Kamailio, although the Contact of your
> 200 OK (hopefully) contains the Asterisk IP.
>
> Please verify that your 200 OK going to the carrier actually does carry a
> Contact header with the Asterisk IP, but if it does, section 12.1.2 of the
> SIP RfC could help when arguing with the carrier.
>
> Regards
> Sebastian
>
> _______________________________________________
> Kamailio (SER) - Users Mailing List
> sr-users at lists.kamailio.org
> 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/20180108/6035056f/attachment.html>