[OpenSER-Users] The Via Header of CANCEL Message

[fancy]

Hi Bogdan:

RFC3665 didn't mention any stateful or stateless 
within all the document.
So I think it is just not covering it.

By the way, is openser a stateless proxy server?
I think it is a stateful proxy server!
Can I config it to be a pure stateless or stateful proxy server?

Thank you.

Best Regards,
Fangyu Ling


> Klaus,
> 
> CANCEL is hop-by-hop only in stateful processing and in this case, yes, 
> it has only on VIA. But if you have stateless processing, CANCEL is 
> end-2-end and it will have multiple VIAs...
> 
> Does 3665 obsoletes stateless SIP or it is just not covering it???
> 
> regards,
> bogdan
> 
> Klaus Darilion wrote:
>> Looks like it is defined clearly and openser is not 100% standard conform.
>>
>> regards
>> klaus
>>
>> fancy wrote:
>>   
>>> Hi Klaus:
>>> RFC 3665 page 54 line 4:
Sorry it's RFC 3261 page 54 line 4:
>>>    A CANCEL constructed by a
>>>    client MUST have only a single Via header field value matching the
>>>    top Via value in the request being cancelled.
>>>
>>> and RFC 3665 at page 53:
Sorry it's RFC 3261 at page 53:
>>>    CANCEL is referred to as a "hop-by-hop" request, since it is
>>>    responded to at each stateful proxy hop.
>>>
>>> and RFC 3665 at page 21:
Sorry it's RFC 3261 at page 21:
>>>    Client: A client is any network element that sends SIP requests
>>>          and receives SIP responses.  Clients may or may not interact
>>>          directly with a human user.  User agent clients and proxies are
>>>          clients.
>>>
>>> So, for my opinion, the role of proxy in this case of RFC 3665 section 3.8 is a client when it sends CANCEL message to Bob.
>>>
>>> If I misunderstand any RFC meanings, please correct me.
>>> Thank you very much.
>>>
>>> Best Regards,
>>> Fangyu Ling
>>>
>>>
>>>     
>>>> fancy wrote:
>>>>       
>>>>> According to RFC 3665 section 3.8 and RFC 3261 section 9,
>>>>> there is only one via header in CANCEL message
>>>>> (message F11, F13 at page 72 of RFC 3665).
>>>>>         
>>>> Hi!
>>>>
>>>> I could find it in RFC 3665, but not in 3261. Where exactly in RFC 3261
>>>> is mentioned that the CANCEL has only 1 Via header?
>>>>
>>>> Further, the example has only one Via header - but I could not find any
>>>> definition if this is a MUST or not.
>>>>
>>>>       
>>>>> How can I remove the 2nd via header?
>>>>>         
>>>> You would have to modify tm module and change the code which generates
>>>> the CANCEL message.
>>>>
>>>> regards
>>>> klaus
>>>>