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Re: time and date

Carl Ellison wrote:
> At 03:58 PM 11/25/97 +0100, Zooko Journeyman wrote:
> >YYYY-MM-DD hh:mm:ss{.s+}
> 
> We used "_" for " " but otherwise this *is* our format.
> Is that one character difference a big deal to you?

For the sake of generality, I would suggest using ' ' instead of '_', but
it's a minor detail that doesn't affect SPKI performance.

As for your claim that this *is* our format, that's not quite right.  The
most recent draft says

"A date field is an ASCII byte string of the form:

   YYYY-MM-DD_HH:MM:SS"

> Here I have to plead guilty.  I spent some of my formative years doing
> performance analysis with rigorous adherence to Statistics practices, 
> where using more digits in a report than the process precision allowed 
> was an unforgiveable sin.

I think I was able to come up with one potential use for sub-second
precision.  I admit that I am threading on thin ice here, but I think this
may be relevant anyway.  

It has been argued that sub-second precision is virtually the same as
on-line checks.  I claim it is not.  Consider a (fictional) real-time
process control system that uses SPKI certs to queue control jobs.  The
precision for some control actions may be in milliseconds.  Applying such
an action at the wrong point in time can be catastrophic.

The jobs will have to be queued in advance, because nobody wants to do SPKI
reduction in real-time, especially not with on-line checks.  So, the SPKI
certificates will contain times that are *local* to the system, but with a
sub-second precision.  They will be issued for a very specific period,
perhaps a repeating period.

Counter-arguments, anyone?  If not, I move that we include the {.s+} part
in the SPKI spec as we else would reduce the usability of SPKI for the
above system.

Regards,
Camillo
-- 
Camillo Särs <Camillo.Sars@DataFellows.com>   Data Fellows Ltd.
F-Secure Support
http://www.Europe.DataFellows.com/      Aim for the impossible and you
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