[Serusers] 487 hop to hop????

Klaus Darilion klaus.mailinglists at pernau.at
Thu Aug 25 16:30:42 CEST 2005

Hi Greg!

Greg Fausak wrote:
> Howdy,
> I've been scouring the RFCs looking for this verbiage.
> One of our developers here is telling me that is a mistake, that the
> 487 needs to come from the far end.  Do you know where I might
> find more information about this topic?

Imagine a forked call. If the call in canceled, ser has to wait for the 
487 messages from all branches. Only after it received the 487 from all 
branches, it will send a 487 to the caller.

> It seems to me that the ser proxy is responding to the cancel with
> a 487.  If I had to make it come from the far end can that be  

What would be the difference if it would come end2end? The caller will 
receive a 487 which will match the call-id and from tag (I think the 
to-tag will be the to-tag of the last 487 received from called parties).

Thus, the caller can not distinghuish if it is generated from ser or 
from a caller.


> accomplished with
> ser?
> Thank you for your feedback,
> Regards,
> ---greg
> On Aug 25, 2005, at 1:47 AM, Klaus Darilion wrote:
>> That's right! CANCEL and 487 are hob-by-hob, if the corresponding  
>> INVITE was forwarded stateful.
>> regards
>> klaus
>> Greg Fausak wrote:
>>> I've got a call trace that shows an INVITE being CANCELed, the
>>> CANCEL is hop to hop.  I had thought the 487 was generated
>>> at the other end and came all the way back, but my call
>>> traces indicate that the 487 is being generated hop to hop as well.
>>> That's not right, is it?
>>> ---greg
>>> _______________________________________________
>>> Serusers mailing list
>>> serusers at lists.iptel.org
>>> http://lists.iptel.org/mailman/listinfo/serusers

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