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Re: time and date

On 12/2/97, men from black helicopters forced Carl Ellison to write:

>At 10:46 AM 11/26/97 +0200, Camillo Sdrs wrote:
>>  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.
>These control functions might need microsecond or better precision.  Yes?

>I personally think that the process control example is far fetched.  If I
>were programming a process control application and I were forced to use
>times, I would prepare a file of control commands, each timed, and then I
>might sign the whole file with a properly empowered key.  I just can't see
>turning each file entry into a separate SPKI certificate.

I agree. I have been thinking about how to interact with remote process control
hardware having done a bit of this in the past. I would send a macro file
that contains a start time and the relative times betwwen commands.
If I needed to specify microsecond times I would adopt a process control
language and send signed commands in that language..

Vinnie Moscaritolo	    tel:  415.524.6222      Pretty Good Privacy, Inc.
Senior Consulting Engineer  main: 415.572.0430      2121 S. El Camino Real

<vinnie@pgp.com>	    web: http://www.pgp.com San Mateo, CA 94403

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