EDIF Version 350/400 and information modelling

Summary form only given. The design and implementation of the EDIF family of standards is based on the use of the specification technique called information modelling. The goal of information modelling is to provide the standards development process with a methodology that will ensure, as far as is possible, that the contents of the standard are correct, consistent and clearly defined. The first part of the paper addresses the high level concepts and goals of information modelling. It looks at the basic mechanisms EXPRESS provides for capturing the essential objects and attributes of a domain and how those objects are inter-related. Above all, it concentrates on how constraints are used to ensure that the information model is explicit and unambiguous. The second part of the presentation focuses on the content of EDIF Version 350 and EDIF Version 400. The general architecture of the new EDIF standard is introduced and used to show how extensions of EDIF into the new domains of PCB and MCM are supported. The solutions adopted in EDIF to ensure a representation with minimal context dependency and hence, it is hoped, minimal ambiguity are highlighted.