Re: [homenet] Ted's security talk at IETF99: DNCP Security

Michael Richardson <> Tue, 01 August 2017 15:38 UTC

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From: Michael Richardson <>
To: Ted Lemon <>
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Date: Tue, 01 Aug 2017 11:38:22 -0400
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Subject: Re: [homenet] Ted's security talk at IETF99: DNCP Security
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Ted Lemon <>; wrote:
    mcr> Christian's comments in DNSSD (which I also watched today) is right though:
    mcr> for many applications in *discovery* is important you probably don't want
    mcr> certs, because they reveal too much, and the relationship is too
    mcr> ephermeral.
    mcr> The link between Dave's Laptop and Dave's Cool Printer is probably
    mcr> longer.

    > Indeed, but we don't want Dave's Laptop going around asking for Dave's Cool
    > Printer when Dave's Laptop is not on the home network where Dave's Cool
    > Printer lives.

You agree that it's a different problem right?

The common part is that one might have a similar set of external (physical) signals.

Should Dave bring his printer to the IETF network, and they happen to
discovery each other via privacy-enhanced dnssd magic (cf: Arthur Clark's
definition of magic), then it would be good that they can prove that it's really them.

Michael Richardson <>;, Sandelman Software Works
 -= IPv6 IoT consulting =-