[Roll] Stephen Farrell's Discuss on draft-ietf-roll-applicability-home-building-09: (with DISCUSS and COMMENT)

["Stephen Farrell" <[e-mail]>]

Stephen Farrell has entered the following ballot position for
draft-ietf-roll-applicability-home-building-09: Discuss

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DISCUSS:
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Please correct me if I'm getting this wrong, I honestly may
have forgotten the plan. My understanding was that RPL and RFC
7416 etc. were approved on the basis that you needed to get to
specific applications of RPL before you could sensibly specify
interoperable security with automated key management (AKM) as
is clearly required by BCP107 and as has been discussed
between security ADs and the ROLL WG numerous times. This is
going back to the 2010 discuss from Tim Polk that I inherited
in 2011, hence me being uncertain if I remember the plan for
sure;-) In any case it seems to me that this draft also
doesn't get us to the point where we have a defined way to do
AKM (Again, sigh.) I also have a set of comments on that below
that I won't make into specific discuss points (at least until
we figure out or re-discover the plan).

So, with that context, and with real regrets for sounding like
an old and broken record, the discuss point: why is this not
the ROLL WG draft where we finally get to specify AKM for RPL?
If your answer is that this is just an applicablilty statement
then I'll ask why it's going for proposed standard, and when
to finally expect the AKM spec for RPL (for this application).


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COMMENT:
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- I don't get how there's an IPR disclosure for this, but
whatever.

- The non-security parts of this were quite a good read.

- 4.1.8: 1st sentence makes no sense. It says RPL does X or
not-X in order to Y. There is no choice but for RPL to do X or
not-X.

- 4.1.8 seems to me to imply that link layer security is
always needed since there can always be some node that will
send an unsecured RPL messsage. If you agree, then I think
that should be made more clear. If you disagree, I'd like to
understand how.

- 4.1.8, I am surprised not to see a recommendation that
separate group keys SHOULD be used for different applications
in the same bulding network. But that may be too fine grained
a recommendation for this document perhaps.

- 5.1.2.1, I think it'd be clearer to say Imin should be
between 10 and 50 ms. The "10 - 50 ms" notation can be
confusing. (Same elsewhere.)

- section 7, 3rd para, "can rely on" is sales language, please
strike that or s/rely on/depend upon/ 

- section 7, 3rd para, last sentence: this is sales language
and should be deleted. Or perhaps s/is/SHOULD be/ would turn
it back into a piece of specification language.

- 7.1 - this is odd text to see in a proposed standard, but I
think it's accurately describing the level of interop to
expect in RPL security, so is probably the right thing to say.
I'd argue that it'd be even better to bluntly admit/say that
there is currently no interoperable automated key management
for RPL. (Same for 7.3) Or, and better, to fix that lack. (See
my discuss point.)

- 7.2, 1st sentence: this is meaningless as I read it - what
are you trying to say?

- 7.2, when a node is stolen, the chances are that any keys
contained in the node are at significant risk of being leaked.

- 7.3, I do not believe that [I-D.keoh-dice-multicast-security] 
is necessarily going to proceed via the DICE WG. Depending 
on it would be fairly high-risk in any case.

- 7.4, last sentence: more sales talk

- 7.5, what is this specifying? I don't get it. Does 7416 set
out what to implement to get interop? (I didn't think so, but
nor does this seem to.)