Re: [homenet] Kathleen Moriarty's Discuss on draft-ietf-homenet-hncp-09: (with DISCUSS)

Juliusz Chroboczek <> Wed, 18 November 2015 15:57 UTC

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Date: Wed, 18 Nov 2015 16:57:43 +0100
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Subject: Re: [homenet] Kathleen Moriarty's Discuss on draft-ietf-homenet-hncp-09: (with DISCUSS)
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>> HNCP is an amazingly flexible protocol, and one that will hopefully be
>> used well beyond it's original area of application.  Many of the possible
>> applications of HNCP don't require DTLS, either because the network is
>> secured at a lower layer, or because they use a different application
>> layer mechanism.

> Which possible applications of HNCP don't require security?

It's not about not requiring security -- it's about mandating this
particular security mechanism.

> If you do have a reason for thinking that DTLS shouldn't be MTI, please
> state it plainly

The mesh community has been using a wide range of techniques for
configuring routers, static configuration, configuration protocols built
into routing protocols, AHCP, etc.  I am currently working on promoting
the use of a subset of HNCP instead.

This work is made difficult by the way the HNCP draft is written -- it is
not immediately obvious that HNCP is a small and elegant protocol, and
that most of the messy baggage is optional.  The general perception is "we
don't need the complexity of HNCP, let's do something ad hoc".  See for

Adding MTI DTLS to HNCP will only make this situation worse: either HNCP
will be ignored by the communities, or the DTLS requirement will be
ignored.  The latter will enforce the (widely held) belief that the IETF
is a fossilised bureaucracy more interested in following its bureaucratic
rules than producing useful documents.  Neither is a desirable outcome.

-- Juliusz