CEST: An expert system function library and workbench for unix® System/C language

Integrating expert system components into production software can be difficult, because environments for developing expert systems typically are not compatible with traditional software-engineering technology. To deal with this problem, we are developing CEST, a C-language expert system toolset. It is a library of inference engines — implemented as C functions that can be called from C programs — and a workbench of knowledge-engineering support tools. CEST allows easy integration of expert system components into C-based software systems, and provides knowledge-engineering support tools analogous to traditional software-engineering support tools. The first tool written for CEST is AVIEN, a backward-chaining attribute-value inference engine. It has been widely distributed within AT&T, and has been used to build both stand-alone expert systems and C-based hybrid systems. In particular, the Quality Assurance Center at AT&T Bell Laboratories is using AVIEN in software tools being developed for quality and reliability analysis.