> Ummm. I'm not comfortable with using a time based period for
> renogatiation.
I think the time based approach sees it more from the angle of the
attacker. You don't want to leave him enough time to crack your encryption
and read happily on in real time, no ?
Since some of the data is actually predictable (as with html), I think you will
actually want larger blocks, and not smaller. Seems like a tradeoff to me.
Most of this encryption stuff is actually only good for delaying a skilled
attacker.
Andreas
