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From: darrell@sdcsvax.UUCP
Newsgroups: comp.os.research
Subject: Re: Keeping Time Synchronous in a Network
Message-ID: <3280@sdcsvax.UCSD.EDU>
Date: Sat, 6-Jun-87 00:38:03 EDT
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Posted: Sat Jun  6 00:38:03 1987
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>range.  Special receivers are available for it.  If you really want to be
>picky, you should correct for the propagation time from the transmitter
>to the receiver, since radio waves only travel 1 foot per nanosecond.
>
>Another thing you might do is check with your local radio astronomers.

The last radio astromoner I talked to that did this synchronized 2 atomic
clocks in the same room, and then picked one of them up and flew it across
the country to be used as the time stamp for the data recorded by the other
radio telescope.

[ This illustrates a basic problem found in distributed systems and not in ]
[ centralized systems.  Keeping a globally consistent view of time is hard ]
[ Those of us without atomic clocks have to rely on approximations, that's ]
[ why all of the fancy protocols are needed.  --DL                         ]