[Cryptography] Best internet crypto clock

Tom Mitchell mitch at niftyegg.com
Wed Oct 8 19:37:36 EDT 2014

On Tue, Oct 7, 2014 at 4:41 PM, Arnold Reinhold <agr at me.com> wrote:

> On Oct 7, 2014, at 3:02 PM, Lodewijk andré de la porte <l at odewijk.nl>
> wrote:
> 2014-10-07 16:21 GMT+02:00 Arnold Reinhold <agr at me.com>:
>> I would envision including a good quality internal clock, set at time of
>> manufacture and non alterable. (When the clock battery dies, the camera is
>> toast.) The camera would periodically or on command output a signed
>> certificate containing the current reading of its internal click and maybe
>> an external nonce like the NIST beacon, which might then be sent to a time
>> stamping service, creating a record of internal clock drift over time.. The
>> camera might store a correction factor, so it could output a UTC time, but
>> the internal clock would be included in any certificate as well.
> ......

> Having the camera and a cock inside the module cuts out all video editing
> techniques. The camera can attest when the entire optical image was
> captured. I’d go further and include a gyro/accelerometer package so a
> panorama could be captured with attestation that the camera was actually
> turned, rather than presented with a moving image.
 A clock that is sufficiently stable for long periods of time and
temperature deltas is nearly
impossible to design.   As soon as one states UTC or somthing common the
answer approaches

However a free running ticker and counter with sufficient bits to never
overflow makes sense.

The Timex on my wrist has a ten year battery... but not enough bits and no
electrical access.

Trivia for digital wrist watches.. the transistors of the clock logic
operate in an analog mode
to allow extreme low power (low clock rate).

In designing clocks one fact is that when broken most are exactly correct
twice a day
and the average of errors will approach zero.  A statistician might
convince a politician
that a broken clock is a perfect clock.
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