Re: [P2PSIP] Ben Campbell's No Objection on draft-ietf-p2psip-share-09: (with COMMENT)

["Thomas C. Schmidt" <[e-mail]>]

Hi Ben,

thanks for your comments. Please see inline.

On 01.11.2016 23:42, Ben Campbell wrote:
> Ben Campbell has entered the following ballot position for
> draft-ietf-p2psip-share-09: No Objection
>
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> ----------------------------------------------------------------------
> COMMENT:
> ----------------------------------------------------------------------
>
> I have a one set of substantive comments/questions, and some editorial
> comments:
>
> Substantive:
>
> - I'm confused about the validation procedure. In step one, is this the
> user name of the user attempting to write the resource? In step 5, I do
> not understand how this terminates. Which ACL item is the "previously
> selected" one. If that refers to the one selected in the last iteration
> of steps 3 and 4, how do you know there are not more ACL items to iterate
> through?
>

You are referring to 6.3 "validating writ access"?

In this case, you receive a store request along with a certificate. In 
step 1, you resolve the user name of the requester, i.e., the user name 
that corresponds to the certificate in the request.

  ... then you identify the user in the ACL and walk up the delegation 
chain.

In step 5, you have arrived at the root of the delegation tree. This is 
the case, when the to_user equals the signer equals the owner of the 
resources (see see Figure 1). This is also how it terminates - the owner 
of the resource is the root of the trust chain.

>
> Editorial:
>
> -1, first paragraph, first sentence: s/that/, which
> -- recurring singular plural mismatch "resources with a variable name".
>

Thanks, fixed.

> -1, 2nd paragraphs: "It transfers the authorization..."
> What is the antecedent for "it"?
>
We meant the "trust delegation mechanism" - but it's ambiguous, you're 
right. Changed to "...based on a trust delegation mechanism that 
transfers the authorization .."

> -3. First paragraph after numbered list, "user called Authorized Peer":
> missing article.
>
Thanks, fixed.

> -3.1, 3rd paragraph: Is the SHALL appropriate? Is an authorized user
> actually required to access the array in the first place?
>

It says "If the data model of the Shared Resource is an array, each 
Authorized..".

So the user is not required to use an array for sharing, but if an array 
is used, write conflicts MUST not be produced.

> - 6.5, first paragraph: Does the MAY grant permission, or is it a
> statement of fact?
>
Good point. The actual statement means that users are enabled to do so. 
So we replace the may by a "can".

> -6.6, paragraphs 3 and 4: Are the MUSTs appropriate? Are there not other
> (perhaps application specific)  reasons one might choose not to write the
> value?
>

I believe the MUST is correct: we're in a section that describes the 
behavior of the storing peer. When receiving a store request, this peer 
should not behave according to its own application semantic, but to the 
common overlay rule.

> -- 2nd paragraph from end: The MUST seems more like a statement of fact.
> (E.g. "The resulting ... integer is used...")
>

Mhmm, I don't think so. These are all iterative decision steps:  try 
(a), then write ... otherwise try (b), then write ... +++ ... otherwise 
refuse.

> - 4.1, last paragraph: s/implementations/implementors
>

Thanks, fixed.

> - 4.2, definition of res_name_ext: The sentence starting with "This name
> serves..." is hard to parse.
>
O.K., changed to "This name is used by the storing peer for validating..."

> -5.1, 4th paragraph (paragraph after example) : s/witch/which
>

Yep, this document was full of witches, but they have been banned now.

Cheers,
  Thomas

-- 

Prof. Dr. Thomas C. Schmidt
° Hamburg University of Applied Sciences                   Berliner Tor 7 °
° Dept. Informatik, Internet Technologies Group    20099 Hamburg, Germany °
° http://www.haw-hamburg.de/inet                   Fon: [phone] °
° http://www.informatik.haw-hamburg.de/~schmidt    Fax: [phone] °