In message <[EMAIL PROTECTED]>, Tom Van Baak writes: >So my question is this. Would it be reasonable >to expect that a generation or two from now, the >common man will need sub-second accuracy?
I've thought about this since your email, and I think we need to rephrase the question subtly in order to get the right perspective. The reason why I want the question rephrased is that peoples lives already depend on a lot of stuff they don't know the details off, algorithms in non-block brake control and airbag release electronics to take a couple of examples, and I have no reason to belive that people would be aware of technology depending on precision of time. People depend on GPS, to the extent where they drive into rivers because their GPS navigator doesn't mention ferries. Ambulances fail to arrive if the GPS system "cannot find the address". Farming implements roam the fields autonomously based on GPS navigation. Cell phones and optical telecom networks only work at all because of tight timing control, most of which is GPS aligned these days. With the new EUROCONTROL plans, peoples lives will very much be dependent on the planes navigation systems working correctly. But all of these systems are characterized by either some supposedly skilled person being in the loop, or trivial visual confirmation being available for error detection. So I think your question should concentrate on the class of uses where peoples lives hinges on precision timekeeping but where there is no skilled pilot who can row the locomotive ashore if/when it fails. It would be a bad design if it allowed that, and I don't think it will happen. >Perhaps it's not the 1.7 ms/cy/cy deceleration >of the Earth that will cause leap second trouble >in the distant future; it's the 60x per N-hundred >years acceleration of precise time in the lives >of the Earth's modern inhabitants that's the >bigger problem. Well, there is a reason why Intel banged their head against the 4GHz barrier and therefore nanoseconds will be the frontier as long as we are into electronics instead of optics. The dangers I see is when people design systems and applications and screw up the handling of time: The problems are all (at) the interfaces. And that is where normal people will get screwed over, when the systems they depend on but don't understand fails to work as advertised because the engineers who implemented them didn't get the interfaces right for details like leapseconds. For some reason, the acronym POSIX comes to mind :-) -- Poul-Henning Kamp | UNIX since Zilog Zeus 3.20 [EMAIL PROTECTED] | TCP/IP since RFC 956 FreeBSD committer | BSD since 4.3-tahoe Never attribute to malice what can adequately be explained by incompetence.
