Re: [ntpwg] NTS: The question of CMS vs. (D)TLS

Florian Weimer <fweimer@redhat.com> Fri, 05 June 2015 12:28 UTC

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Date: Fri, 05 Jun 2015 13:49:12 +0200
From: Florian Weimer <fweimer@redhat.com>
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Subject: Re: [ntpwg] NTS: The question of CMS vs. (D)TLS
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On 06/05/2015 11:58 AM, kristof.teichel@ptb.de wrote:

> (2) Draft for utilization of NTS for NTP 
> (draft-ietf-ntp-using-nts-for-ntp)
> - In this draft, we intend to specify that for bootstrapping, an 
> implementation MUST support the use of the CMS-based message exchanges, as 
> described in the informational appendix mentioned above.
> - We will further specify that an implementation MAY also support other 
> methods for bootstrapping, for example exchanging the necessary data via 
> DTLS or DANE. Any such method needs to fulfill the requirements given in 
> the main draft.

This seems okay to me, as long as there is a clean separation between
the negotiation and post-negotation phase, and the session ticket is
treated as an opaque blob (of variable length).  I would have to see the
actual language to be sure.

-- 
Florian Weimer / Red Hat Product Security
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