Re: [6tisch] Adam Roach's Discuss on draft-ietf-6tisch-minimal-security-13: (with DISCUSS and COMMENT)

Michael Richardson <mcr+ietf@sandelman.ca> Fri, 01 November 2019 21:46 UTC

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From: Michael Richardson <mcr+ietf@sandelman.ca>
To: Benjamin Kaduk <kaduk@mit.edu>
cc: Adam Roach <adam@nostrum.com>, 6tisch@ietf.org, draft-ietf-6tisch-minimal-security@ietf.org, pthubert@cisco.com, 6tisch-chairs@ietf.org, The IESG <iesg@ietf.org>
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Date: Fri, 01 Nov 2019 17:46:15 -0400
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Subject: Re: [6tisch] Adam Roach's Discuss on draft-ietf-6tisch-minimal-security-13: (with DISCUSS and COMMENT)
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Benjamin Kaduk <kaduk@mit.edu> wrote:
    >> §8.1.1:
    >>
    >> > o The Uri-Path option is set to "j".
    >>
    >> COAP URIs are generally subject to BCP 190 restrictions, which would
    >> require the path to either be provisioned, discovered, or under the
    >> ".well-known" tree. The use of a reserved domain name here may change
    >> the rationale; but for the sake of not establishing a precedent for
    >> path squatting in CoAP, this document needs to clearly explain the
    >> rationale of why BCP 190 should not apply in this case. Alternately,
    >> the implied URI can be changed to something like
    >> "coap://6tisch.arpa/.well-known/j"

    > Note also the parameter update exchange describe in Section 8.2, where
    > the joined node is supposed to act as a CoAp server and expose the "/j"
    > resource.  The justification of the reserved domain name does not seem
    > to apply to that case, which seems to suggest that .well-known will be
    > needed.

I've added that the 6LR should locate this at the "6tisch.arpa" hostname.
This isolates the "/j" from any other uses of CoAP on the node.

If that's not acceptable, then we could live with .well-known, as the 6LR
has already joined, and it can negotiate for bandwidth, etc.

--
Michael Richardson <mcr+IETF@sandelman.ca>ca>, Sandelman Software Works
 -= IPv6 IoT consulting =-