Re: [Dtls-iot] Secure Time (again)

Michael StJohns <msj@nthpermutation.com> Tue, 11 August 2015 14:35 UTC

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To: Hannes Tschofenig <hannes.tschofenig@gmx.net>, Eric Rescorla <ekr@rtfm.com>
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From: Michael StJohns <msj@nthpermutation.com>
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Date: Tue, 11 Aug 2015 10:35:35 -0400
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Subject: Re: [Dtls-iot] Secure Time (again)
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On 8/11/2015 10:28 AM, Hannes Tschofenig wrote:
> Thanks, Ekr.
>
> On 08/11/2015 03:33 PM, Eric Rescorla wrote:
>> This is already done.
> While I understand the reason for removing the functionality from the
> ServerHello I still think it is a needed functionality for many IoT
> deployments to obtain time information (without having to fall back to NTP).
>

Yup - but not all IOT devices will do DTLS or TLS.  And time in DTLS or 
TLS isn't "secure".

I think for this version, you should assume that DTLS and TLS will not 
be a source of time and write accordingly.

Mike