View
310
Download
1
Category
Preview:
Citation preview
DATA COMMUNICATIONS
-is the process of transferring digital information (usually in binary form) between two or morepoints.
1837Samuel F.B. Morse invented the telegraph
With the telegraph, dots and dashesare transmitted across a wire throughelectromechanical induction.
18371840 Originally, the first telegraph was invented
by Sir Charles Wheatstone and Sir WilliamCooke. In 1840, Morse secured an Americanpatent for the telegraph.
1837184018441849
The first slow-speed telegraph printer wasinvented in 1849, but it was not until 1860that high-speed (15 bps) printers wereavailable.
18371840184418491850
The Western Union Telegraph Companywas formed in Rochester, New York forthe purpose of carrying coded messagesfrom one person to another.
183718401844184918501874
Émile Baudot invented a telegraph multiplexer,which allowed signals from up to 6 telegraphmachines to be transmitted simultaneouslyover a single wire.
1837184018441849185018741876
18991920
The first commercial radio stations wereinstalled, allowing the transmission ofinformation across large spans of water.
1837184018441849185018741876
18991920
1940
Bell Laboratories developed the firstspecial-purpose computer usingelectromechanical relay.
1837184018441849185018741876
18991920
19401951
Built by the Remington Rand Corporation,the UNIVAC computer was the firstmass-produced electronic computer.
1837184018441849185018741876
18991920
19401951
1968
Until 1968, the AT&T operating tariff allowed only equipment furnished by AT&T to beconnected to AT&T lines.
1837184018441849185018741876
18991920
19401951
1968
A landmark Supreme Court decisionthe Carterfone decision (1968), allowed non-Bell companies to interconnect to the vastAT&T communications network. Thisdecision started the interconnect industry,which has led to competitive data communications offerings by a large numberof independent companies.
-creates the sets of rules and standards for graphics,document exchange and related technologies. TheISO is responsible for endorsing and coordinating thework of other standards organization.
-consists of government authorities andrepresentatives from many countries. It is now thestandards organization of the United Nations anddevelops the recommended sets of rules andstandards for telephone and telegraph communications.
-is the official standards agency for the United Statesand is the U.S. voting representative for ISO.
-is a U.S. organization that establishes andrecommends industrial standards. The EIA isresponsible for developing the RS (recommendedstandards) series of standards for data andtelecommunications.
Recommended