[WG-IMS] Scope of IMS in OpenSIPS - RFC
Bogdan-Andrei Iancu
bogdan at opensips.org
Wed Dec 6 11:53:11 UTC 2023
Hi Carsten,
Gotcha you! basically the MMTel AS should implement some predefined
logic (like routing between devices, to other networks) with the
addition of those listed service - and the settings for the service
resides in HSS (via Sh). I hope I got it right :)
Best regards,
Bogdan-Andrei Iancu
OpenSIPS Founder and Developer
https://www.opensips-solutions.com
https://www.siphub.com
On 05.12.2023 14:33, Carsten Bock wrote:
> Hi,
>
> The central role of the MMTel is purely to
> provide supplementary services like call-forwarding, call-barring,
> etc. As a result, it only has SIP- (ISC-Interface towards the S-CSCF)
> and the Sh-Interface (for storing and retrieving the settings from the
> HSS).
>
> You can find a list of supplementary services here:
> https://www.gsma.com/newsroom/wp-content/uploads//IR.92-v18.0-3.pdf
> (Page 24)
>
> You can actually create most of the supplementary services in a few
> hundred lines of OpenSIPS.cfg - the complex part is restoring and
> retrieving the settings using the Sh-Interface.
>
> IR.92 compliance is a widespread request when it comes to VoLTE
> deployments.
>
> Thanks,
> Carsten
>
>
> --
> Carsten Bock I Chief Technology Innovation Officer & Founder
>
> ng-voice GmbH
>
> Trostbrücke 1 I 20457 Hamburg I Germany
> T +49 1511 5942983 I www.ng-voice.com <http://www.ng-voice.com/>
>
> Registry Office at Local Court Hamburg, HRB 120189
> Managing Directors: Dr. David Bachmann, Carsten Bock, Quirin Maderspacher
>
>
>
> Am Di., 5. Dez. 2023 um 11:50 Uhr schrieb Bogdan-Andrei Iancu
> <bogdan at opensips.org>:
>
> Hi Carsten,
>
> OK, thanks for the heads-up on the HTTP/2, we can have it on the
> list with a lower priority, maybe subject to future release,
> depending on the overall volume of work.
>
> Now, on the AS part, I understand MMTel is a global standard for
> IMS, but (please baer with me as a rookie in the area) do you have
> some links to some document to give a quick understanding on the
> MMTel specs for the AS part? More or less, what I'm trying to
> understand here is what kind of interface the AS should provide
> (for routing and service creation) when comes to call handling. On
> the Sh interface, we just need to be careful with the Diameter
> implementation (to support all the Sh mappings).
>
>
> Thanks and regards,
>
> Bogdan-Andrei Iancu
>
> OpenSIPS Founder and Developer
> https://www.opensips-solutions.com
> https://www.siphub.com
>
> On 04.12.2023 17:32, Carsten Bock wrote:
>> Hi,
>>
>> (removed users@ - to avoid political discussions)
>>
>> I would also suggest the following initial scope:
>> - IMS-Core (P-/I-/S-CSCF). I would not spend too much time on
>> HTTP/2 for now. In most deployments, Diameter is still the way to
>> go - even though I've seen more and more offerings of HTTP/2 /in
>> addition/ to Diameter. In a worst-case scenario, you could always
>> deploy a DRA to translate from Diameter to HTTP/2.
>> - A MMTel AS for providing essential services - preferably with a
>> native Diameter Sh Interface for storing/retrieving supplementary
>> service settings.
>>
>> This would allow you to provide essential VoLTE services. If
>> you're an MVNO, Emergency services are handled by the hosting
>> MNO, and other services like SRVCC are losing importance as we speak.
>>
>> Just my initial thoughts,
>> Carsten
>>
>>
>> --
>> Carsten Bock I Chief Technology Innovation Officer & Founder
>>
>> ng-voice GmbH
>>
>> Trostbrücke 1 I 20457 Hamburg I Germany
>> T +49 1511 5942983 I www.ng-voice.com <http://www.ng-voice.com/>
>>
>> Registry Office at Local Court Hamburg, HRB 120189
>> Managing Directors: Dr. David Bachmann, Carsten Bock, Quirin
>> Maderspacher
>>
>>
>>
>> Am Mi., 29. Nov. 2023 um 16:39 Uhr schrieb Bogdan-Andrei Iancu
>> <bogdan at opensips.org>:
>>
>> Hi Giovanni,
>>
>> Thanks for the feedback here, a valuable one as usual :).
>>
>> On the HSS, what you are saying aligns with the my own
>> thoughts - that its functioning logic is somehow outside the
>> our scope here, but we need to pay attention to the
>> interfacing (DIAMETER or HTTP2.0).
>>
>> Now, on the AS side - as I understand, it holds whatever
>> custom logic the operator may have in routing and proving
>> services (included VAS's). So to say, I see it as a highly
>> programmable component. And if so, what we need to provide
>> here is probably a very high level interface / API to allow
>> call manipulation in a very abstract way... :-/ ??
>>
>> Best Regards,
>>
>> Bogdan-Andrei Iancu
>>
>> OpenSIPS Founder and Developer
>> https://www.opensips-solutions.com
>> https://www.siphub.com
>>
>> On 29.11.2023 11:11, Giovanni Maruzzelli wrote:
>>> First of all:
>>> CONGRATULATIONS to the OpenSIPS community !!!
>>> (I believe this is the first step of a long and
>>> satisfying journey)
>>>
>>> On the topic:
>>> in addition to the CSCF component, I would like to see
>>> efforts on the AS (Application Server) component of the IMS
>>> infrastructure.
>>>
>>> The AS is probably way the simplest of it all, it will
>>> probably require the least modifications/additions to OpenSIPS.
>>>
>>> But I would say AS will be crucial to a lot of people/use cases.
>>>
>>> While for sure there will be a lot of cases for our
>>> community to build the voice/video complete IMS
>>> infrastructure on top of private 5G networks in enterprises
>>> and public administrations, I see as very much relevant also
>>> the use case of building infrastructure to provide
>>> additional third party services to big carriers, and to big
>>> carriers partners.
>>>
>>> Also, AS is the correct and manageable way to provide
>>> additional services even if you build the core IMS
>>> infrastructure.
>>>
>>> About HSS: this is the sancta sanctorum of a carrier/provider
>>> Apart from the venerable fraunhofer java implementation, now
>>> we can count on the flexible java implementation in
>>> https://github.com/nickvsnetworking/pyhss with a lot of
>>> features, good performances, and actually built for production.
>>>
>>> I would say better we concentrate on accessing the various
>>> different protocols of HSS (diameter/http2) from the various
>>> components (each component in IMS access HSS with a
>>> different interface with different vocabularies and actions.
>>>
>>> MGCF/MGW, if needed, will be a natural extension of our
>>> CSCF/AS architecture.
>>>
>>> Just my two cents, to keep the ball rolling,
>>>
>>> Congratulation again,
>>>
>>> -giovanni
>>>
>>>
>>> On Tue, Nov 28, 2023 at 2:02 PM Bogdan-Andrei Iancu
>>> <bogdan at opensips.org> wrote:
>>>
>>> Hi all,
>>>
>>> (disclaimer : cross lists posting is not a good practice
>>> - we will do this only to catch the attention and get
>>> momentum with this initial topic)
>>>
>>> As a first step here, is to work out the scope of the
>>> IMS implementation in OpenSIPS. IMS is a vast concept,
>>> with SIP and non-SIP components, and we want to
>>> understand and agree on which components of IMS may be
>>> subject of work from the OpenSIPS perspective. For
>>> example, we do consider the CSCF as a must here, but we
>>> may explore the HSS, AS, MGW or other components.
>>>
>>> From the OpenSIPS perspective, we look for IMS
>>> components which are SIP related. At least as a starting
>>> point. So, the first obvious candidate is the *Call
>>> Session Control Function (CSCF)*. And here we need to
>>> look into and address the specific functionalities of
>>> each sub-component:
>>> * P-CSCF
>>> * I-CSCF
>>> * S-CSCF
>>>
>>> Again, these are the pretty obvious components, still
>>> may look into and evaluate (if of an interest of the
>>> OpenSIPS IMS implementation) areas as:
>>> * HSS (from interconnection perspective)
>>> * MGCF / MGW (from interconnection perspective)
>>> * SIP AS
>>> * others ?
>>>
>>> Any feedback (with explanations and arguments) about
>>> what we should consider for our IMS implementation is
>>> more the welcome. I set here just a simple starting
>>> point, with no limitations or so. Feel free to
>>> contribute to the topic
>>>
>>>
>>> Best regards,
>>>
>>> --
>>> Bogdan-Andrei Iancu
>>>
>>> OpenSIPS Founder and Developer
>>> https://www.opensips-solutions.com
>>> https://www.siphub.com
>>>
>>> _______________________________________________
>>> Wg-ims mailing list
>>> Wg-ims at lists.opensips.org
>>> http://lists.opensips.org/cgi-bin/mailman/listinfo/wg-ims
>>>
>>>
>>>
>>> --
>>> Sincerely,
>>>
>>> Giovanni Maruzzelli
>>> OpenTelecom.IT
>>> cell: +39 347 266 56 18
>>>
>>
>> _______________________________________________
>> Wg-ims mailing list
>> Wg-ims at lists.opensips.org
>> http://lists.opensips.org/cgi-bin/mailman/listinfo/wg-ims
>>
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.opensips.org/pipermail/wg-ims/attachments/20231206/cde9fa7a/attachment-0001.html>
More information about the Wg-ims
mailing list