CAD data exchange standards

This chapter and the two subsequent ones will tackle the increasingly important problems of data exchange and interchangeability of software. A standard of some kind is essential to any transfer of data from one program to another. The stream of binary digits constituting the data cannot be interpreted by the receiving program unless its format or coding scheme is known. It may seem trivial to say so but the only reason why standards are not an issue when programs in the same CAD/CAM system interchange data is that the people who write the programs are constrained by their management to agree a standard. When the programs are supplied by different companies there is no common management and standards become an issue and a problem. In this chapter we will consider a variety of standards which have been developed to help programs communicate with each other. When transfers of data take place between different computers in different places, hardware such as magnetic tape units and telephone lines are involved. We will describe some hardware standards in “Hardware data exchange standards” on page 203.