[Serusers] SIP to AS communication

Greger V. Teigre greger at teigre.com
Mon Oct 9 10:46:48 CEST 2006


Hi Dragos,
Thanks for your update on the project. Really interesting stuff!
An idea: Once we release 0.10, maybe we could create a tar package with 
an "IMS version" of SER, where the modules are included, maybe some 
extra docs, etc.  Or are you planning to make available the IMS modules 
as part of 0.10??

FHoSS sounds interesting, is that a full-flegded Diameter server 
according to HSS specification??  Are there any peculiarities that make 
it non-suitable for general Diameter use (i.e. non-IMS)?

To IPsec: To me the IPsec requirement is a typical aspect of the 
carrier-centric approach of IMS. Supposedly both IPv4 and v6 can be run 
independently and together, but the NAT-traversal issues with IPsec is 
maybe even more difficult than for SIP (believe me, I have spent lots of 
time on both...). I haven't been able to test my Nokia E70 SIP client's 
IPsec NAT traversal capabilities yet (as I don't have testing access to 
an IMS proxy :-).  On 3G I presume most carriers have non-NATed 
networks, but the E-series has WiFi capabilities and one of the things 
trumpeted with IMS is the cross-access-network nature of IMS services. 

Have you tried TLS in 0.10 the way you describe?

g-)

Dragos Vingarzan wrote:
> ...This is re-post, because the previous one was sent from the wrong 
> mail-address and now it awaits moderations... sorry for duplicates if 
> eventually it gets accepted.
>
> Hi all,
>
> Yes, IMS is quite bloated. However, for the past years we did some 
> work at FOKUS related to it and it will be soon released. It does not 
> have ALL what IMS demands, but it is a start and we hope that you 
> guys, if you think that something more is required, could help us 
> achieve that.
>
> I am attaching the proof that it will be, on 16.11.2006 (it is also an 
> invitation for you to participate, but I am not making publicity on 
> this list ;-) http://www.fokus.fraunhofer.de/event/ims_ws_06/ ). If 
> you need further info, feel free to contact us.
>
> To offer you some info about it before this date, we will release a 
> bundle of modules:
> - cdp - for efficient diameter communication in SER (stands for 
> CDiameterPeer)
> - pcscf - implementing some of the P-CSCF functionality
> - icscf - -//- ICSCF
> - scscf- -//- SCSCF
> - isc - for Initial Filter Criteria Triggering and communication 
> between S-CSCF and AS
> - sip2ims - a simple MD5 to AKA authorization gateway
>
> All these modules at the moment are relatively stable on SER 
> 0.10.99-dev41. But the problem there is that the diameter 
> functionality is integrated into the core. We are working now on 
> stabilizing the cdp as a module in 0.10.99-dev45. Once we succeed, I 
> hope that the modules will be usable with any new plain-CVS SER release.
>
> Also, we will give away FHoSS - our Java HSS implementation together 
> with the included pure Java - Java Diameter Peer - diameter 
> functionality.
>
> So, you will have a basic IMS system to play with. Almost the same 
> Open IMS Core is used in the ETSI/TISPAN IMS Benchmarking effort as a 
> reference implementation for the System Under Test (look for WorkItem 
> 06024).
>
> Don't expect too much, but at least now we have full Cx support, 
> Initial Filter Criteria triggering, ISC support, AKA authentication, 
> IPSec in transport mode with clients, etc... and all this plus the 
> wonderful SER script functionality.
>
> Oh yeah :)... and don't expect carrier-grade quality though. These are 
> research projects and we care more about experimenting with the latest 
> features than the 99.999%. For that stability, as Jiri implies, 
> Tekelec probably has (or will have) a good solution, but we can't do 
> that as our budgets are much lower than those of the SPs or TEMS.
>
> As Andrey pointed out, we are not the only ones doing this, but I hope 
> that we could converge.
>
> And Jiri is right about the complexity. There are at least 4 
> components that have to work together. For SigComp, because of it's 
> complexity, I was considering TLS with compression. This could also 
> replace the IPSec transport mode tunnel for security, which could be 
> difficult on some embedded devices. Any thoughts on this? Anyway, 
> SigComp is asked mainly by the mobile operators only and we should not .
>
> Looking forward for you comments,
> Dragos Vingarzan
>
> Jiri Kuthan wrote:
>> Just a warning small in size but I guess big in the impact. I think 
>> people kind of underappreciate the effort which has to be taken. If 
>> you consider all the 3gpp complexity (sigcomp as a prime example, one 
>> of many being real non-trivial), size of mobile networks for which 
>> the system has to be running, number of interfaces to speak over and 
>> achieve interoperability (management, diameter, applications,  cdr 
>> processing...), routing features (the 'scim' feature with
>> which this discussion began)...
>>
>> I occur to know Tekelec has gone through this exercise and generating
>> a reasonable result has cost quite an investment.
>>
>>
>> At 07:19 06/10/2006, Andrey Kuprianov wrote:
>>  
>>> Hi, I suppose you need to develop modules for all the the x-CSCF + 
>>> AS (where x-CSCF is P-CSCF, S-CSCF or I-CSCF). You see, the 
>>> functionalities/features that x-CSCF and application servers require 
>>> (for instance, P-headers or querying for subscriber information from 
>>> HSS) are not available in SER. That's why you need to make your own 
>>> modules *all the way*. As for HSS, i dont think you need to make 
>>> some special super DIAMETER-enabled database. In my (an in many 
>>> other people's btw) point of view a simple database, like MySQL is 
>>> more than capable of storing subscriber info or initial filtering 
>>> criterias (iFC --> im talking about SCIM/SIMF). If you are really 
>>> set to develop IMS on SER, then maybe you can start with SER 0.8.14. 
>>> You can still find decent development documentation for it. As for 
>>> later versions, I dont think any good docs are yet available 
>>> (someone, please, correct me if im wrong)     
>>
>> The documentation is being worked on, but for the moment you are 
>> unfortunately correct.
>>
>>  
>>> Just for your info, INT (France) joint with France Telecom are 
>>> developing IMS on SER as of now (dont know if it's going to be 
>>> commerial or open-source. Contact them if you are interested, maybe 
>>> you can even help them develop it further :). Plus, Focus is also 
>>> set to develop a commercial version of IMS for SER and, although, 
>>> Focus said that their IMS will be available in the last quarter of 
>>> this year, but nothing's been released yet. :(
>>>     
>>
>> That's fantastic news, I'm looking forward to GPL contributions from 
>> these
>> very respectable institutions. This is really a big piece of work and 
>> I am
>> enormously positive about every single new piece of the puzzle.
>>
>> -jiri
>>
>>  
>>>   Good luck,     Andrey. On 10/6/06, Kamal.Mann at t-systems.com 
>>> <Kamal.Mann at t-systems.com> wrote: > Hi All > We are using SER as 
>>> CSCF which communicates with HSS and Application Server. >        
>>> Whenever a UA sends a request to SER then it should go to some 
>>> specific table and look for services assigned to that particular UA. 
>>> >        If UA is authorize to use that service than SER send 
>>> this to AS. >        AS then send this request/response to 
>>> Serving SER (S-CSCF) which further serves that UA. > I need your 
>>> suggestions for the same that what kind of module we need to develop 
>>> for this scenario or any valuable suggestions. > > Thanks in 
>>> anticipation > Kamal Mann > > 
>>> _______________________________________________ > Serusers mailing 
>>> list > Serusers at lists.iptel.org > 
>>> http://lists.iptel.org/mailman/listinfo/serusers > > > </x-flowed>
>>> _______________________________________________
>>> Serusers mailing list
>>> Serusers at lists.iptel.org
>>> http://lists.iptel.org/mailman/listinfo/serusers
>>>     
>>
>> -- 
>> Jiri Kuthan            http://iptel.org/~jiri/
>> _______________________________________________
>> Serusers mailing list
>> Serusers at lists.iptel.org
>> http://lists.iptel.org/mailman/listinfo/serusers
>>
>>   
>
>



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