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Data body mealplan |
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Here is an example of how the data body is fed by routine day-to-day activities, a data body meal plan:
Breakfast: phone calls, drive GPS (global positioning system) equipped car, emerge from surveillance camera equipped subway, go online, send E-mails, complete online registration forms, receive faxes
Lunch: pay lunch with credit card, use your customer card when shopping, use mobile phone, pass through biometric access controls, use smart card
Afternoon snack: visit doctor, file insurance claim
Dinner: respond to TV commercials, complete income tax form, visit chat rooms, use free web mail. Programme phone wake-up call.
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Chappe's fixed optical network
Claude Chappe built a fixed optical network between Paris and Lille. Covering a distance of about 240kms, it consisted of fifteen towers with semaphores.
Because this communication system was destined to practical military use, the transmitted messages were encoded. The messages were kept such secretly, even those who transmit them from tower to tower did not capture their meaning, they just transmitted codes they did not understand. Depending on weather conditions, messages could be sent at a speed of 2880 kms/hr at best.
Forerunners of Chappe's optical network are the  Roman smoke signals network and Aeneas Tacitus' optical communication system.
For more information on early communication networks see Gerard J. Holzmann and Bjoern Pehrson, The Early History of Data Networks.
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