history of modems
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Histor ofModemsof being online
http://docslide.us/documents/history-of-modem.html
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Modems grew out of the need toconnect teletype machines overordinary phone lines instead of more
expensive leased lines which hadpreviously been used for currentloop-based teleprinters and
automated telegraphs.
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George Stibitzconnected aNew Hampshire
teletype to acomputer inNew or! "ityby a subscriber
telephone line
in #$%&
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'n #$%() '*M adapted this technologyto their unit record e+uipment andwere able to transmit punched cards at
, bits/second.
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Mass-produced modems in the nited States began aspart of the SG0 air-defense system in #$1)connecting terminals at 2arious airbases) radar sites)and command-and-control centers to the SG0 director
centers scattered around the .S. and "anada.
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'n #$3,) 454 introduced the *ell #&( 6ata7hone) which set the standard for (&&-baud
full-duple8 modems. ntil #$1%) 454 held amonopoly on the phone system in the nitedStates) so only 454 could pro2ide modemsto wor! on its networ!. 4he monopoly sti9edmodem inno2ation until the #$31 "arterfonedecision opened the mar!et for third-party
phone de2ices) albeit in a limited fashion.
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Non-*ell companies began selling computer modems. ne of the most notablefor our purposes was the Hayes 1&-#&() a (&&-baud *ell #&(-compatiblemodem that happened to be the ;rst modem created for a personal computer.6ale Heatherington
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The rst smartmodem
'n #$1#) 6.". Hayes ssociates introduced its seminal Hayes Stac!Smartmodem. 4he (&&-baud modem was the ;rst to integrate its
own command set -- one that became an industry standard.
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Early home PC modems
Modems for the early personal computers of the late #$>&s and early#$1&s were a mi8 of direct-connect
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The early !M PC era
?rom the mid-#$1&s onward)'*M 7" clones dominated the7" mar!et) leading to a new
era of internal 'S
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"oice modems and smart modems
'n the mid-#$$&s
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The land of#$%bps
'n the late #$$&s)modemmanufacturers
bumped upagainst thetheoretical andlegal limits of
analog telephonedata transferspeeds.
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&'! modems
4hough dial-up modemswere once standard in
7"s) they are becomingscarce due to thepredominance ofbroadband internetaccess. "ompanies still
sell modems that connectthrough e8ternal serialports and internal 7"'slots) but one commonapproach is to plug in atiny S* modem
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!eyond dial-upHa2ing reached the limits of analog modem technology)companies tried 2arious new approaches to sate the public@sdemand for e2er-faster modem speeds. 4he ;rst alternati2e wasall-digital phone lines
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http://www.techradar.com/news/internet/getting-connected-a-history-of-modems-3>%>$
http://www,.rad.com/networ!s/,&&/modems/history.htm
http://en.wi!ipedia.org/wi!i/*ulletinBboardBsystem
http://en.wi!ipedia.org/wi!i/Modem
http://www.infoworld.com/d/networ!ing/history-modems-3&-years-going-online-
>(5currentC,5lastC#Dslideshow4op
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