The Internet Assigned Number Authority (IANA) Header Field Parameter Registry for the Session Initiation Protocol (SIP)
draft-ietf-sip-parameter-registry-02

[Note]: 'Approved with two RFC Editor Notes:

Universal Resource -> Uniform Resource in title

Specification Required -> IETF Consensus in parameters doc.  This was the
intent, that header parameters (like the values) must include publication
in an IETF RFC, not in a non-IETF spec.' added by Allison Mankin

[Ballot comment]
> 3.  Use of the Registry
...
>  Registered SIP header field parameters and parameter values are to be
>  considered "reserved words". In order to preserve interoperability,
>  registered parameters and parameter values MUST be used in a manner
>  consistent with that described in their defining RFC.

The MUST above reads a bit like that for smb's evil bit.
I.e. is this a requirement for implementations of all registered params?
What is it doing here?

[Ballot comment]
In the parameter registry document, I think this text:


  Parameters that can appear in different header fields MAY have the
  same name. However, parameters that can appear in the same header
  field MUST have different names.

needs to be clarified.  I read it as saying that the registry may include the same
name multiple times, provided that each instance is attached to a different
header field.  If a parameter with a specific name is already associated with a
specific header, a new parameter may not be registered under that name. 
If that is correct, using language that describes the registry actions is probably
a good idea for this document; if it is not correct, I am not sure what to suggest.

While I don't wish to block the document on this, I do wonder why the uri parameter
registry did not include columns for "applies to SIP URIs" and "applies to SIPS URIs"
instead of advice to consult the specification.  I would certainly not suggest allowing
the same parameter to appear twice with different semantics, one for SIP and one for
SIPS, but the choice to elide the applicability from the registry seems odd.

[Ballot comment]
In the parameter registry document, I think this text:


  Parameters that can appear in different header fields MAY have the
  same name. However, parameters that can appear in the same header
  field MUST have different names.

needs to be clarified.  I read it as saying that the registry may include the same
name multiple times, provided that each instance is attached to a different
header field.  If a parameter with a specific name is already associated with a
specific header, a new parameter may not be registered under that name. 
If that is correct, using language that describes the registry actions is probably
a good idea for this document; if it is not correct, I am not sure what to suggest.

IANA Last Call Comments:
Note the spelling error in paragraph 3 (dissimialr)

Upon approval of this document, the IANA will create a new sub-registry for sip header field parameters.  This registry will be placed at the following:

[Note]: 'Note sip-parameter-registry has a garbled format at the end and
both documents need a revised id-nits check because I waited to
Last Call them until knowing that IANA was going to be able to
handle large registries again.' added by Allison Mankin