[Gen-art] Gen-art LC review of draft-saintandre-impp-call-info-02

[Elwyn Davies <[e-mail]>]

I am the assigned Gen-ART reviewer for this draft. For background on
Gen-ART, please see the FAQ at

<http://wiki.tools.ietf.org/area/gen/trac/wiki/GenArtfaq>.

Please resolve these comments along with any other Last Call comments
you may receive.

Document: draft-saintandre-impp-call-info-02.txt
Reviewer: Elwyn Davies
Review Date: 23 April 2013
IETF LC End Date: 14 May 2013
IESG Telechat date: (if known) -

Summary: Ready.  See the generic issue with the IANA registry mentioned 
below.

Major issues: None

Minor issues: None

Nits/editorial comments:
Generic comment about SIP Header Field Parameters registry: For the 
uninitiated this registry is rather opaque.  Some parameters, such as 
the Call-Info purpose parameter for which an extra value is defined 
here, have predefined values.  However the predefined values themselves 
are not in the registry and just giving a whole RFC reference for places 
where values are defined is not very helpful. For example, in the case 
of Call-Info, the initial predefined values of purpose are buried in the 
Call-Info rule in the ABNF in Section 25.1 of RFC 3261;  also, Section 
20.9 describes the predefined values (such as "icon") as 'parameters' 
rather than values of 'purpose'.  It would probably be helpful to either 
improve the references in the registry table or actaully quote the 
possible predefined values in the table.