Re: Response overrides local tag?

Kalman, Ranga,

I made some changes to the code in CVS which I believe will help your case. 
Please update and see if it works for you

Regards,

Jeroen

----- Original Message ----- 
From: "M. Ranganathan" <[email protected]>
To: "Kalman Lau" <[email protected]>
Cc: <[email protected]>
Sent: Tuesday, June 27, 2006 6:45 AM
Subject: Re: [nist-sip] Response overrides local tag?


> Kalman,
>
> What you are doing seems to be appropriate. You should let the stack 
> assign the To tag for the Refer. The REFER should be created after the ACK 
> is received (or after the OK is sent at any rate). The From and  To tag 
> of the Refer should match the From and To of the  OK/ACK.  If you let the 
> stack manage your tag assignments, this will be the case. If this is the 
> case, the  202 Accepted should have the same From/To tags as the ACK and 
> you should not have any problems.
>
> Perhaps the REFER is being created before the OK is sent out when the 
> Dialog is still in the early state or perhaps you are using message 
> factory to create the Request? Can you check on that? However, I agree 
> that the stack should do more to help with tag management here. Are you 
> using Dialog.sendRequest(transaction) to actually send the request out? If 
> so, I can assign the Refer To tags when the Refer is actually sent out 
> rather than rely upon the applicatoin to do the right thing  prior to 
> sending the request(i.e. I can override whatever tag the application 
> assigns in this case). I will make this change and commit to the 
> repository soon.
>
> Regards,
>
> Ranga
>
>
> Kalman Lau wrote:
>
>> For the following sequence...
>>
>> Caller        App
>> ------        ---
>>   |            |
>>   | INVITE     |
>>   +----------->|
>>   |            |
>>   |     Trying |
>>   |<-----------+
>>   |    Ringing |
>>   |<-----------+
>>   |         OK |
>>   |<-----------+
>>   |            |
>>   | ACK        |
>>   +----------->|
>>   |            |
>>   |      REFER |
>>   |<-----------+
>>   |            |
>>   | Accepted   |
>>   +----------->|
>>   | NOTIFY     |
>>   +----------->|
>>   |            |
>>
>> I used the Dialog generated from the initial INVITE to send the REFER 
>> request.   Was this appropriate?  If so, I am having the following 
>> problem...
>>
>> The SIPClientTransaction was woken up to process the 202-Accepted 
>> response, it proceeds to trigger the SIPDialog to update its local tag as 
>> follows:
>>
>> +-> UDPMessageChannel.run() line: 452
>>   +-> SIPClientTransaction.processResponse(SIPResponse, MessageChannel) 
>> line: 1252
>>     +-> SIPClientTransaction.processResponse(SIPResponse, MessageChannel, 
>> SIPDialog) line: 521
>>       +-> SIPDialog.setLastResponse(SIPTransaction, SIPResponse) line: 
>> 2244
>>         +-> SIPDialog.setLocalTag(String) line: 1302
>>
>> (Note:  line numbers from JAIN_SIP_1_2 as of last week...)
>>
>> But being a server dialog, SIPDialog.setLastResponse() sets the local tag 
>> using the response's TO header tag, thus overriding what appears to be 
>> its original, valid local tag.
>>
>> Subsequently, when the app attempts to respond to the NOTIFY with a 
>> 200-OK ( using the NOTIFY request's transaction), 
>> SIPServerTransaction.sendResponse(Response) line 1252 throws a 
>> SipException with message "Response tags dont match with Dialog tags".
>>
>> Is the noted issue about the local tag a bug?  Or am I misusing something 
>> else?
>>
>> Kalman
>>
>>------------------------------------------------------------------------
>>
>>_______________________________________________
>>nist-sip mailing list
>>[email protected]
>>http://www-x.antd.nist.gov/mailman/listinfo/nist-sip
>>
>
>
> -- 
> M. Ranganathan
> Advanced Networking Technologies Division,
> National Institute of Standards and Technology (NIST),
> 100 Bureau Drive, Stop 8920, Gaithersburg, MD 20899. tel:301 975 3664 , 
> fax:301 590 0932 http://w3.antd.nist.gov/
> Advanced Networking Technologies For the People!
>
> _______________________________________________
> nist-sip mailing list
> [email protected]
> http://www-x.antd.nist.gov/mailman/listinfo/nist-sip