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From: geof@apolling.UUCP.UUCP
Newsgroups: mod.protocols.tcp-ip
Subject: Station wagon full of bits
Message-ID: <8703242139.AA00170@apolling.imagen.uucp>
Date: Tue, 24-Mar-87 16:39:06 EST
Article-I.D.: apolling.8703242139.AA00170
Posted: Tue Mar 24 16:39:06 1987
Date-Received: Thu, 26-Mar-87 02:42:39 EST
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 > In article <8703220422.AA13307@buita.bu.edu> jsol@buit1.bu.EDU writes:
 > >        From: Scott Earley <EARLEY@BITNIC>
 > >
 > >        ... Tables
 > >        for all sites on the Ohio side of the PSU-Ohio link will be put
 > >        on tape and mailed overnight to a pre-appointed individual who
 > >        will reintroduce them into the network from there.
 > >        ...
 > >
 > >That's right.  Mag tape.
 > >
 > >--Daemon
 > 
 > Never underestimate the bandwidth of a station wagon full of magtapes!
 > 

Well, we can't resist this, can we.  Back of the envelope calculations
for a station wagon full of bits transmitted from the east coast to the
west coast follow.  Apologies for any naivitee about magtapes -- I don't
use them often and never learned all the sordid details.

    Station wagon: 5' X 5' X 3' trunk
    Transit time: 4 days = 345 600 s
     (might add a day on each side to copy the data to & from tape)
    Data:
        1 magtape, 12"X1" reel, 1000' of tape, 9600 bpi, 9 tracks
            => 12*1000*9600*9 = 129.6 E 6 bits
        5*5*36 = 875 magtapes in trunk

        => 875*129.6 = 113.4 E 9 bits

    Throughput:
        113.4e9 b / 345600 s = 328,125 b/s

Hmm.... better than the arpanet.... how much does a station wagon
cost these days, anyway...

Corrections welcome (they might as well be, I'm sure there will
be some!),

- Geof