The hash function must be cryptographically strong, e.g. MD5. Certificate Authority CAD Software Computer Aided Design is the use of computers to assist the design process. It is normally possible to generate engineering drawings to allow the final design to be constructed. The CAD program will often include various forms of analysis to test out the design. For example, an engineering CAD system may include structural analysis to check the load bearing capabilities of the design.
Electronic CAD can include circuit simulation.
A standard for running external programs from a World-Wide Web HTTP server. CGI specifies how to pass arguments to the executing program as part of the HTTP request. It also defines a set of environment variables. Commonly, the program will generate some HTML which will be passed back to the browser but it can also request URL redirection. A CGI program can be any program which can accept command line arguments.