Re: Executing Encrypted Code

[ph@netcom.com (Peter Hendrickson)]

At 8:31 PM 12/19/1996, Timothy C. May wrote:
>At 7:34 PM -0800 12/19/96, Peter Hendrickson wrote:
>> You could also timestamp the software so that it only runs for a given
>> length of time.  This will encourage people to upgrade regularly.  ;-)

> Or to reset their clocks. Which is what many of us do when software is
> about to "expire."

You are right that this only works in instances where the customer just
needs a little prodding to get the upgrade and not in instances where
the customer might put up with significant inconvenience to avoid it.

However, why not use "beacons"?  The clock could have a built-in timer
that needs to be reset once a month from an authenticated source.  This
assumes the presence of net connectivity, but that's not a terrible
assumption.

Peter Hendrickson
ph@netcom.com