Formal Methods and Standards - An Idiosyncratic View

Abstract

Many of the reported experiences in the industrial use of formal methods concern the development of products or product families, where the utility of the method is linked to direct savings in development costs or improved assurance of quality. However, one other area in which formal description techniques make a valuable contribution is in the development and documentation of International Standards, where the cost of using formal methods can be paid off both through increased quality of products that implement a given standard, and through the improved inter-operability of different implementations that comes from having a precise definition of the expected behaviour of a conforming implementation. The process of standardization within ISO/IEC is complex, and affords the oppertunity to use formal methods at different stages and in different ways. This paper illustrates how formal methods have been used in the development of two standards, the computer graphics standard, GKS, and the multi-media standard, PREMO. Formal methods have been used at different points during their development. This paper concludes with an appraisial of the work done and some thoughts about future directions. 2nd BCS-FACS Northern Formal Methods Workshop Formal Methods and Standards-An Idiosyncratic View The cycle of ballot, comment, revise, re-ballot, is a long one, but it does ensure that technical material is given thorough review. Published standards are reviewed at least every 5 years, at which stage the standard may be confirmed, revised, or withdrawn. There are three principles that underlie ISO/IEC standardization (adapted from [21]): Consensus views of manufacturers, vendors and users, consumer groups, testing laboratories, governments, engineering professions and research organizations are all taken into account. All may be represented in national standards-making bodies (such as BSI) and all have the opportunity to participate in the work. Industry-wide International Standards are meant to be global solutions to satisfy industries and customers world wide. Voluntary standardization is market driven and therefore based on voluntary involvement of all interests in the market place.