Design and Assurance of Control Software

When I was EIC of TSE and before, software design approaches were matched with the type of application. Since that time, software has become a major component in the control of potentially dangerous systems and has grown enormously in size. Most of these systems require high assurance of important properties, such as safety and security, and sometimes, require regulatory certification before they can be used. Today, however, such assurance is usually very expensive and limited in its power. This short paper proposes a change in how software is designed that can greatly simplify the development, assurance, and maintenance and evolution of critical control software.