15 May
2008
15 May
'08
7:45 a.m.
El Thursday 15 May 2008 05:39:32 Allan Chao escribió:
Dear All:
I have found there are some devices can't process two 180 ringing after
use OPENSER to do parallel forking, so, i have a idea that is used
OPENSER to delete To tag in the To header before relay it , and it works
well with eyebeam. But i can't find any spec to support my idea because it
is against "early dialog" prograss and my question is
how does UE(eyebeam or some client) to create dialog if there is no any To
tag in 180 ringing but 200 OK has in the latter ? i think the UA will
generate local ring tone but no any dialog after receives 180 ringing with
no To tag? is it right ? thanks,
A "180 Ringing" without To tag is completely anti RFC 3261 compliant so you
shouldn't do it:
8.2.6.2 Headers and Tags
...
However, if the To
header field in the request did not contain a tag, the URI in the To
header field in the response MUST equal the URI in the To header
field; additionally, the UAS MUST add a tag to the To header field in
the response (with the exception of the 100 (Trying) response, in
which a tag MAY be present). This serves to identify the UAS that is
responding, possibly resulting in a component of a dialog ID. The
same tag MUST be used for all responses to that request, both final
and provisional (again excepting the 100 (Trying)).
If you have a device not allowing various 180 with different To tag, this is,
a device not allowing parallel forking, then it's a bug in that device.
--
Iñaki Baz Castillo
ibc(a)in.ilimit.es