The design of systems has been greatly influenced by computers. For instance, the development of automated design and drafting came about in the 1950's and 1960's within the military and US Air Force. In the search for new defense systems, an innovative system was created that used a visual display to transmit vital, spatial information regarding a possible enemy threat. Since then the technology has continuously evolved at an accelerated rate, and spawned the fields of Computer Graphics (CG) and Computer-aided Design (CAD). Computer-aided manufacturing (CAM) was a well-developed industry which used computers to aid in production of metal parts. CAD was not more than an idea until CAM catalyzed its existence. Although CAD systems had been developed, graphical input data was cumbersome until Ivan Sutherland's sketchpad was developed in academia. These systems were almost all proprietary until AutoDesk brought CAD to the home market and onto the personal computer, streamlining the design process.


Halfway through the $20^{th}$ century, the United States was faced with two major international struggles: in June of 1948 the Berlin Blockade occurred, a major crisis of the Cold War; just two years later, the Korean war broke out in June of 1950. During these times it became imperative for the US to build an efficient military defense \cite[1]{sage}. A new type of defense gave promise on April $20^{th}$, 1951, when a team of electrical engineers from MIT and radar engineers from Air Force's Cambridge Research Laboratories demonstrated how computers could be used to defend the continent from an airborne attack:


\begin{quotation}
For the first time, radar data on an approaching ``enemy'' aircraft had been sent over telephone lines and entered into an electronic digital computer, which had almost instantaneously calculated and posted instructions directing the pilot of a ``defending'' aircraft to his target \cite[1]{sage}.
\end{quotation}

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\img{/app/assets/paper/ibm-sage.jpg}
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\includegraphics{images/sage.ps} \\
\addcontentsline{lof}{figure}{The Semi-Automatic Ground Environment (SAGE) computer was used by the US Air Force.} 
The Semi-Automatic Ground Environment (SAGE) computer was used by the US Air Force. \\
(source: http://www.computermuseum.li/Testpage/IBM-SAGE-computer.gif)
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This system was the world's first to use a computer to generate graphics. The US Air Force used this command and control system known as Semi-Automatic Ground Environment (SAGE) to display radar data and relevant information on an interactive \emph{cathode-ray tube}. Information that traveled over a network between computers was then processed in real-time, enabling Air Force personnel to detect intruding aircraft and respond accordingly \cite[1]{bozdoc}. SAGE was a system that later spawned what became the foundation for the rapidly-growing fields of computer networking and computer graphics.


Computer Graphics and Networks