Re: [ippm] AD review: draft-ietf-ippm-more-twamp

[Al Morton <[e-mail]>]

Hi Lars,

Thanks for your comments.

The final wording might benefit from
an exchange on this one in particular:

At 03:58 PM 4/27/2009, Lars Eggert wrote:
>...Section 4.1., paragraph 1:
> >    This section describes REQUIRED extensions to the behavior of the
> >    TWAMP Sender.
>
>   Section 2 said that this entire draft specifies OPTIONAL
>   functionality.   This section says that the following extensions are
>   REQUIRED. That's a bit of a mismatch. Either this entire document is
>   now required to implement TWAMP, or the extensions are OPTIONAL, but
>   implementations that chose to implement them need to do these. Please
>   make this more clear.

This mode of operation is OPTIONAL of course.  But, once the
Server and Control-Client have agreed to use this mode,
then the Session-Sender and the Session-Reflector MUST
conform to the provisions of this mode (operate using the
Unauthenticated packet format). What seems to be missing
in RFC 2119 is a "CONDITIONALLY REQUIRED" term.

So, here's a paragraph I suggest to add to section 4:

This section describes OPTIONAL extensions. When the Server
has identified the ability to support the mixed security mode,
the Control-Client has selected the mixed security mode in its Set-Up-Response,
and the Server responds with a zero Accept field in the Server-Start message,
then these extensions are conditionally REQUIRED.

It will be good to sort this out, because we'll need this
wording in other TWAMP features.

Al