Iñaki Baz Castillo wrote:
> 2010/7/6 Paul Kyzivat <pkyzi...@cisco.com>:
>>> What does it mean "a subscription and invite usage are sharing a
>>> dialog"? does it mean two dialog, an INVITE dialog and a SUBSCRIBE
>>> dialog, sharing the same From/to-tags and Call-ID? how could it be
>>> useful such "experiment"??
>> It means one dialog (Callid, from-tag, to-tag) and two distinct usages of
>> that - e.g. INVITE and SUBSCRIBE.
>>
>> The easiest way to encounter that in the wild is to send a REFER in an
>> INVITE-dialog-usage, thus getting an (implicit) subscribe-dialog-usage to
>> the refer event in the same dialog.
>
> Yes, I know that usage. But in the above text I understood sending a
> initial SUBSCRIBE with same dialog info than an existing INVITE
> dialog. :)
If you send an "initial" SUBSCRIBE with the dialog id of an existing
dialog, then it is not really an "initial" SUBSCRIBE - it is an
in-dialog SUBSCRIBE. Its "initial" WRT the dialog-*usage* establishment,
but not WRT the *dialog* establishment.
Its technically valid according to 3261 & 3265, though frowned upon and
to be forbidden by 3265bis.
Thanks,
Paul
_______________________________________________
Sip-implementors mailing list
Sip-implementors@lists.cs.columbia.edu
https://lists.cs.columbia.edu/cucslists/listinfo/sip-implementors
