[homenet] Benoit Claise's Discuss on draft-ietf-homenet-dncp-09: (with DISCUSS and COMMENT)

["Benoit Claise" <[e-mail]>]

Benoit Claise has entered the following ballot position for
draft-ietf-homenet-dncp-09: Discuss

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DISCUSS:
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Other ADs focused on the protocol specific points. So let me focus on
something else.
The applicability section doesn't answer my questions: when to (re-)use
this protocol?
Note that the write-up mentioned ANIMA.

I see the protocol description:

   DNCP is designed to provide a way for each participating node to
   publish a set of TLV (Type-Length-Value) tuples, and to provide a
   shared and common view about the data published by every currently or
   recently bidirectionally reachable DNCP node in a network.

I see, under the applicability section, under which conditions to use
it.
Basically, suitable to exchange any TLV tuples, infrequently. 

However, this applicability section doesn't tell me when to re-use DNCP
(or define a profile for it).
What about the environment: home network versus LAN versus WAN? How big
can the network be?
Does the technology matter? 
Regarding transport, it's basically any transport, unicast or multicast,
right? (DNCP can be used in networks where only unicast transport is
available.  While DNCP uses the least amount of bandwidth when multicast
is utilized)
All devices in a DNCP network must be DNCP node?
I have a DNCP network with profile 1, can I use the same DNCP network
with profile 2?
IANA and enterprise specific TLVs?
UDP is fine as a transport?
What if I know my topology already (I see later: "may use multicast for
Trickle-based shared state dissemination and topology discovery") 
etc.  

Just reading the intro and the applicability, I scratched my head: it's
so generic, should I even consider it for ANIMA?

A few paragraphs, somewhere in the document, would solve my DISCUSS:
- this protocol should be used to exchange the following type of data
...
- it's envisioned that this generic state synchronization protocol will
be used in the following environments ...
- potential DNCP-based protocols include ...


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COMMENT:
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- I would agree with Alvaro, when he wrote: "In general, I found the text
not straight forward or easy to understand." Potentially due to the
structure.

- I hope that a document about manageability considerations (see
https://tools.ietf.org/html/rfc5706#appendix-A) will follow.

- As reported by Victor, part of his OPS DIR review:
Found In Nits:

(https://tools.ietf.org/idnits?url=https://tools.ietf.org/id/draft-ietf-homenet-dncp-09.txt)

    - Use of lower case not with SHOULD statement (see Paragraph 2,
    Section 4.5)

    - Flagged spacing items (Lines 197, 252, 256 and 260)


Section 3: Overview 
   
    paragraph 2: their addresses may be manually configured or they may

       be found by some other means defined in a later specification

    ** This text is not quite clear.  Is it the author’s intention that
    the reader assume the other means will be part of a specific DNCP
    profile specification, a revision of the DNCP document or a
    different type of document.? ***


Section 4.2: Data Transport 

    Paragraph 4 / Part “Multicast+Unicast”

     <old> It is used to send Network State TLVs every now and

          then, as specified in Section 4.3

    <suggested> It is used to send Network State TLVs
    periodically, as specified in Section 4.3

    <reason>  Avoids using an idiom to express sending frequency
    in text.

 
Section 8.1 Pre-Shared Kay Trust Method

    ** Would it be within the DNCP document to discuss how PSKs are
    stored (as to not be externally accessed) or would it be to the
    profile to defined that level? ***