Re: [sipcore] draft-roach-sipcore-rfc3265bis-00 - Section 4.5

["Ian Elz" <[e-mail]>]

 Adam,

1st of 2 responses

Easy one first.

This sounds fine - better than I would have expressed it.

Ian

-----Original Message-----
From: Adam Roach [mailto:[e-mail]] 
Sent: 14 August 2009 20:57
To: Ian Elz
Cc: [e-mail]; Christer Holmberg
Subject: Re: draft-roach-sipcore-rfc3265bis-00

Ian Elz wrote:
>
> Sections 4.5 and 4.5.1 define how to target SUBSCRIBE to a device 
> using gruu. Is it worth including in this section that to target a 
> SUBSCRIBE to a dialog at the device you need to use the Target-Dialog 
> header? The use of T-D would depend upon the event package but 
> including it here would provide a reminder that event packages should 
> consider this if necessary.
>

I agree that this kind of guidance would indeed be useful. I've added
some text to 4.5:

   This dialog-sharing technique has also historically been used as a
   means for targeting an event package at a dialog.  This usage can be
   seen, for example, in certain applications of the REFER method
   [RFC3515].  With the removal of dialog re-use, an alternate (and more
   explicit) means of targeting dialogs needs to be used for this type
   of correlation.  The appropriate means of such targeting is left up
   to the actual event packages.  Candidates include the "Target-Dialog"
   header field [RFC4528], the "Join" header field [RFC3911], and the
   "Replaces" header field [RFC3891], depending on the semantics
   desired.  Alternately, if the semantics of those header fields do not
   match the event package's purpose for correlation, event packages can
   devise their own means of identifying dialogs.  For an example of
   this approach, see the Dialog Event Package [RFC4235].