Assignment No. 1
Brief History of Data Communication
Camille A. Bonito
Florinda H. Oquindo
TIMELINE OF HISTORY OF DATA COMMUNICATION
Telegraph defined from the Greek... TELE = Afar GRAPHOS = Write
First telegraph in Bavaria. Samuel Soemmering. Used 35 wires with gold electrodes in water. Detection at distant end 2000 feet away was by the amount of gas caused by electrolysis.
First telegraph in the USA. Harrison Dyar sent electrical sparks through chemically treated paper tape to burn dots and dashes.
Samuel F.B. Morse and Alfred Vail were issued a patent for the first practical telegraph based on electromagnets. Relays were used every 10 miles to repeat the signals. In Morse coding there are 11 different characters between American and European codes.
Samuel Morse and Alfred Vail introduce a Morse printer that uses ink and electromagnets to print dots and dashes on paper tape.
David Hughes, a music professor in Kentucky uses a vibrating spring tuned to a specific pitch to synchronize the sending and receiving teleprinter with use a code invented by him.
Telegraph becomes the greatest means of communications ever. Over 83,000 miles of wire in the USA alone dedicated to telegraph. At the same time development of the telephone begins.
J.M.E. Baudot in France invents the multiplex telegraph system where at least 4 stations can transmit simultaneously (actually serially) through the use of a distributor. The transmitters are like a miniature piano with five keys. Each combination of keys equals a character. Paper tape is used as the printed media.
Baudot's 5 unit code forms the basis for the european standard CCITT International Telegraph Alphabet No. 1 (ITA-1)
Donald Murray improves the 5 unit code with new character assignments and adds two shifts. This becomes the basis of CCITT Alphabet No. 2 (ITA-2) which is still in use one