[Serusers] rfc 3262 support

[Greger V. Teigre]

I think the idea is that a proxy can send a provisional response to the 
UAC and thus take responsibility for the transaction towards the (real) 
UAS, just like sending a 100 Trying... before forwarding. The UAS has 
not yet received the INVITE (or whatever message we are talking about) 
and thus to tag is not yet set.
g-)

Klaus Darilion wrote:
> Hi Kamal!
>
> I reconsidered by previous answer and found that there is no Cseq 
> Problem as CSeq may have gap.
>
> But reading your snippet: I've never seen any client yet sending 
> provisional responses without to-tag. Thus, even if the proxy could 
> generate reliable responses it wouldn't be used often.
>
> regards
> klaus
>
> Kamal.Mann at t-systems.com wrote:
>> Hi Darilion
>> Please check the following snippet from rfc-3262
>> "An element that can act as a proxy can also send reliable provisional
>> responses.  In this case, it acts as a UAS for purposes of that
>> transaction.  However, it MUST NOT attempt to do so for any request that
>> contains a tag in the To field.  That is, a proxy cannot generate
>> reliable provisional responses to requests sent within the context of a
>> dialog.  Of course, unlike a UAS, when the proxy element receives a
>> PRACK that does not match any outstanding reliable provisional response,
>> the PRACK MUST be proxied."
>>
>> Regards
>> Kamal Mann
>>
>> -----Original Message-----
>> From: Klaus Darilion [mailto:klaus.mailinglists at pernau.at] Sent: 
>> Thursday, October 19, 2006 3:03 PM
>> To: Greger V. Teigre
>> Cc: Mann, Kamal; serusers at lists.iptel.org
>> Subject: Re: [Serusers] rfc 3262 support
>>
>> AFAIK PRACK is a client feature and is end to end. Thus, ser supports 
>> PRACK as any other generic SIP request.
>>
>> Maybe you could fake PRACK requests or responses between a PRACK capable
>>
>> client and the proxy, but this will cause end-to-end CSeq mismatch 
>> and would require a dialog stateful proxy to adapt the CSeqs.
>>
>> regards
>> klaus
>>
>> Greger V. Teigre wrote:
>>> AFAIK, this RFC is not implemented yet. As for a list, there is none 
>>> right now, but it's on the to-do list :-)
>>> g-)
>>>
>>> Kamal.Mann at t-systems.com wrote:
>>>> Hi All
>>>>
>>>> Do SER supports 'rfc 3262 Reliability of Provisional Responses in 
>>>> SIP'? Is there any list of standards supported by SER available??
>>>>
>>>>  
>>>>
>>>> Regards
>>>>
>>>> Kamal Mann
>>>>
>>>>  
>>>>
>>>>
>> ------------------------------------------------------------------------
>>>> _______________________________________________
>>>> Serusers mailing list
>>>> Serusers at lists.iptel.org
>>>> http://lists.iptel.org/mailman/listinfo/serusers
>>>>   
>>>
>> ------------------------------------------------------------------------
>>> _______________________________________________
>>> Serusers mailing list
>>> Serusers at lists.iptel.org
>>> http://lists.iptel.org/mailman/listinfo/serusers
>
>