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Re: [openpgp] time representation in OpenPGP

Benjamin Kaduk <kaduk@MIT.EDU> Tue, 05 July 2016 01:59 UTC

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Date: Mon, 04 Jul 2016 21:59:05 -0400
From: Benjamin Kaduk <kaduk@MIT.EDU>
To: "brian m. carlson" <sandals@crustytoothpaste.net>
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Cc: IETF OpenPGP <openpgp@ietf.org>
Subject: Re: [openpgp] time representation in OpenPGP
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On Sun, 3 Jul 2016, brian m. carlson wrote:

> On Sun, Jul 03, 2016 at 03:57:31PM +0200, Kristian Fiskerstrand wrote:
> > On 07/03/2016 03:48 PM, Salz, Rich wrote:
> > > I suggest we use ASN1 generalized time (which has only a couple of
> > > bytes overhead) or ISO 8601 profiled to be like the ASN1 format:
> > > YYYY-MM-DD-HH:MM:SS.sss with fraction optional.
> > >
> >
> > ASN1 sounds complex in this case, some form of ISO8601 variant might be
> > helpful.
> >
> > Alternatively expanding the size of the value from 32 bits to 64 bits
> > might be easier to deal with for backwards compatibility reasons.
>
> I'd strongly recommend simply using a 64-bit (signed?) integer.  It's
> compact, avoids time zones (which are a source of bugs), and is the
> logical extension.

I've seen 64-bit integer measuring in quanta of 100ns in a few places,
FWIW.  The finer granularity doesn't really eat into the usable range, for
a couple axes of future-proofing.

-Ben

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