[OpenSIPS-Users] About obstacles to implement the matched Id in event header of NOTIFY(REFER)
Bogdan-Andrei Iancu
bogdan at opensips.org
Tue Aug 16 08:23:10 UTC 2022
Vlad, haven't you looked into this some time ago?
Best regards,
Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
https://www.opensips-solutions.com
OpenSIPS Summit 27-30 Sept 2022, Athens
https://www.opensips.org/events/Summit-2022Athens/
On 8/15/22 4:32 PM, Li Cai wrote:
>
> Hi Bogdan,
>
> Yes, I’m trying to figure out a way to implement correct Id in event
> header of NOTIFY for REFER. Can I ask for the suggestion on how to
> move forward?
>
> Thanks,
>
> Li
>
> *From:*Bogdan-Andrei Iancu <bogdan at opensips.org>
> *Sent:* August 9, 2022 5:00 AM
> *To:* OpenSIPS users mailling list <users at lists.opensips.org>; Li Cai
> <Li.Cai at comtech.com>
> *Subject:* Re: [OpenSIPS-Users] About obstacles to implement the
> matched Id in event header of NOTIFY(REFER)
>
> *WARNING: External Email: Exercise Caution*
>
> Hi Li,
>
> If I understand correctly, you try to improve the b2b support in
> OpenSIPS in order to properly handle that NOTIFY for REFER, right ?
>
> Regards,
>
> Bogdan-Andrei Iancu
> OpenSIPS Founder and Developer
> https://www.opensips-solutions.com <https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.opensips-solutions.com%2F&data=05%7C01%7CLi.Cai%40comtech.com%7Caa7c80c3658c4d3945f408da79e59f87%7Ca9a26e696ae040c1bd801ca6cc677828%7C0%7C0%7C637956324395132469%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=VIMtpd2MeOVvrbL2OZTpZTgE9WkrNqkAhpblo%2BHzEDE%3D&reserved=0>
> OpenSIPS Summit 27-30 Sept 2022, Athens
> https://www.opensips.org/events/Summit-2022Athens/ <https://gcc02.safelinks.protection.outlook.com/?url=https%3A%2F%2Fwww.opensips.org%2Fevents%2FSummit-2022Athens%2F&data=05%7C01%7CLi.Cai%40comtech.com%7Caa7c80c3658c4d3945f408da79e59f87%7Ca9a26e696ae040c1bd801ca6cc677828%7C0%7C0%7C637956324395132469%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=CANaT64J1XgnShZ9q4gOIfT5PHG8LRUoB%2BSKkGFrUMk%3D&reserved=0>
>
> On 7/22/22 11:02 PM, Li Cai wrote:
>
> Hi experts,
>
> I’m working on the implementation for ‘2.4.6 Multiple REFER
> Requests in a Dialog’ of RFC3515 in a B2B SIP Proxy. Right now, I
> got stuck with two problems in the solution. Please see the
> paragraph from RFC-
>
> A REFER creates an implicit subscription sharing the dialog
>
> identifiers in the REFER request. If more than one REFER is issued
>
> in the same dialog (a second attempt at transferring a call for
>
> example), the dialog identifiers do not provide enough information to
>
> associate the resulting NOTIFYs with the proper REFER.
>
> Thus, for the second and subsequent REFER requests a UA
> receives in a
>
> given dialog, it MUST include an id parameter[2] in the Event
> header
>
> field of each NOTIFY containing the sequence number (the number
> from
>
> the CSeq header field value) of the REFER this NOTIFY is associated
>
> with. This id parameter MAY be included in NOTIFYs to the first
>
> REFER a UA receives in a given dialog. A SUBSCRIBE sent to refresh
>
> or terminate this subscription MUST contain this id parameter.
>
> Different from the definition in RFC, the NOTIFY forwarded by the
> proxy contains the same Id in Event header as the other side.
> Please see the below chart –
>
> B2BProxy
>
> |
>
> <- REFER 2 (Cseq=2) | <-REFER 1
> (Cseq=1003)
>
> . . . | . . .
>
> ->NOTIFY 1 (event:*id=2*) | ->NOTIFY 2 (_event*:id=2*)_
>
> The current problem is, the above NOTIFY on the right side should
> _include ‘id=1003’ instead of ‘id=2’_.
>
> The solution I’m trying is as in the following flow –
>
> 1. get CSeq 1 of REFER 1 in route[b2b_request]{} ->
>
> 2. get CSeq 2 of REFER 2 in local_route{}, then
> save the pair(key=CSeq2, value=CSeq1) in a map set->
>
> 3. get Id from NOTIFY 1 event in
> route[b2b_request]{} ->
>
> 4. use Id as key then get matched CSeq1 from the
> map set, use remove_hf() and append_hf() to modify the event
> header in local_route{}
>
> My two questions are:
>
> 1. To transfer Cseq 1 from step1 to step2, I tried a variable in
> the AVP type but it didn’t work. The script variable can work
> but it doesn’t fit because the processing is based on per
> request. Can I ask if you have any suggest on how to transfer
> the value from route[b2b_request]{} to local_route{}?
> 2. In the step2, I tried to create and operate a JSON map set to
> save the CSeq pairs. But the JSON data didn’t work for me.
>
> My source :
>
> $json(csList) = ””; #
> Initialize the data set, not sure if it’s correct
>
> $json(csList/”$cs”) = “$avp(csNum)”;
>
> The error I got:
>
> ERROR:core:do_assign: setting PV failed
>
> ERROR:core:do_assign: error at
> /usr/local//et/opensips/opensips.cfg:531
>
> Thank you very much for the help! Any your suggests are very
> welcomed.
>
> Thanks,
>
> Li
>
> NOTICE TO RECIPIENT: This email, including attachments, may
> contain information which is confidential, proprietary,
> attorney-client privileged and / or controlled under U.S. export
> laws and regulations and may be restricted from disclosure by
> applicable State and Federal law. Nothing in this email shall
> create any legal binding agreement between the parties unless
> expressly stated herein and provided by an authorized
> representative of Comtech Telecommunications Corp. or its
> subsidiaries. If you are not the intended recipient of this
> message, be advised that any dissemination, distribution, or use
> of the contents of this message is strictly prohibited. If you
> received this message in error, please notify us immediately by
> return email and permanently delete all copies of the original
> email and any attached documentation from any computer or other
> media.
>
> _______________________________________________
>
> Users mailing list
>
> Users at lists.opensips.org <mailto:Users at lists.opensips.org>
>
> http://lists.opensips.org/cgi-bin/mailman/listinfo/users <https://gcc02.safelinks.protection.outlook.com/?url=http%3A%2F%2Flists.opensips.org%2Fcgi-bin%2Fmailman%2Flistinfo%2Fusers&data=05%7C01%7CLi.Cai%40comtech.com%7Caa7c80c3658c4d3945f408da79e59f87%7Ca9a26e696ae040c1bd801ca6cc677828%7C0%7C0%7C637956324395132469%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&sdata=5WE09OJAM1ASRTd%2BRNiRXbOtXqFZyvynlPhNScOyybk%3D&reserved=0>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opensips.org/pipermail/users/attachments/20220816/e9794f1f/attachment-0001.html>
More information about the Users
mailing list