Subject: Re: [Gen-art] Gen-art review of draft-krb-wg-ananon-12.txt

From: Jeffrey Hutzelman <[email-masked]>
Date: Fri, 08 Oct 2010 12:06:48 -0400

--On Friday, September 10, 2010 04:27:38 PM +0100 Elwyn Davies 
<[email-masked]> wrote:

Thanks for the review, Elwyn.

> Minor Issues:
> s4.3, para 3:  The 'MUST' is not enforceable:  certainly the client needs
> to check it has got what it asked for but this isn't a protocol
> requirement.  Maybe s/the client MUST check to make sure/it is essential
> for the client to check/
>
> s6, para 4: As in s4.3, the first MUST is not enforceable.s/MUST/needs to/
>
> s8, para 2:  same problem again.

Contrary to popular belief, requirements language does not have to be 
"enforceable" in order to be meaningful and appropriate.  In each of the 
cases cited, "MUST" is used to call out behaviors which are required 
because they are essential to the security of the protocol extensions 
defined in this document.  I don't see any need for a change here.

> Nits/editorial:

Except for one, the items in this part of your review are straightforward 
and will be taken care of in the next update.  The exception is this:

> s4.1, para 6: It might be helpful to give a little more guidance about
> what might reveal the client's identity, or at least provide a pointer
> back to s3's list of what *can* be included.

Unfortunately, we can't, and section 3 contains no such list. 
Authorization data is an open-ended space in the protocol for carrying 
information related to authorization; there's no way to enumerate which AD 
types might reveal the client's identity.  That's going to be dependent on 
the particular extensions involved, which may or may not be standardized, 
and quite possibly by policy.

-- Jeff