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Article #237

Re: Synchonizing watches

#237
From: pds
Date: Tue, 08 Sep 1992 13:37
39 lines
1631 bytes
In article <1992Sep4.174143.13747@hubcap.clemson.edu>, mln@sunkj.larc.nasa.gov (Michael L Nelson) writes:
> I must be missing something here, because this looks quite simple.
> 
> -A & B already know this procedure.
> 
> A: says "Bing" to B
>    B responds with "Bing" to A
> 
> this is ABBA time - the total delay

Yup.
 
> A:
> 1. says "Bong"

at time T say, message arrives at B at T+AB

> 2. waits, say N minutes (N > ABBA) 
> 3. says "Bong" again

at time T+N say, message arrives at B at T+N+AB

> B already knows what N is, and can then determine
> What AB is (Bong2 - Bong1 - N)

No - he just receives two messages N minutes apart:
(Bong2-Bong1-N) = T+N+AB-(T+AB)-N = 0, not AB

> (un)synchronized ;-) 

Patrick

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From: pds@epcc.edinburgh.ac.uk
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Subject: Re: Synchonizing watches
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Date: 8 Sep 92 13:37:34 GMT
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