Re: [openpgp] time representation in OpenPGP

Werner Koch <> Tue, 05 July 2016 08:07 UTC

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From: Werner Koch <>
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Subject: Re: [openpgp] time representation in OpenPGP
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On Sun,  3 Jul 2016 15:38, said:

> This wraps around in early 2106, if my math is correct.

Right, in the morning of February 7, 2106.  But only if the same
calendar and time notation will be used in 90 years.  I do not think we
should make assumption for such a long time span.  Will computers and
protocols be similar how we currently think about them?  Who was able to
imagine today's technology back in 1926?  Nowadays technologies develops
even more rapid than we assumed 40 years ago.

> Would someone like to propose an alternate representation of time for
> RFC 4880bis?  Or is there a clear argument for keeping it as-is?

I'd say to keep the format as it is now.  If in 50 years there is still
a need for the OpenPGP protocol, a re-chartered WG could easily introduce
a, say, v8 key and signature format with a 40 bit value for seconds
since Epoch or whatever format will be en vogue by then (maybe keeping
the 32 bits and switching the Epoch to 2063-04-05).

If we really want to introduce this now, I would suggest to add an extra
zero octet right before any timestamp.  This can eventually be used as a
40 bit timestamps with only minor code changes.



Die Gedanken sind frei.  Ausnahmen regelt ein Bundesgesetz.
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