Exception handling in workflow management systems

摘要

Fault tolerance is a key requirement in process support systemsn(PSS), a class of distributed computing middleware encompassingnapplications such as workflow management systems and process centerednsoftware engineering environments. A PSS controls the flow of worknbetween programs and users in networked environments based on an“metaprogram” (the process). The resulting applications arencharacterized by a high degree of distribution and a high degree ofnheterogeneity (properties that make fault tolerance both highlyndesirable and difficult to achieve). We present a solution fornimplementing more reliable processes by using exception handling, as itnis used in programming languages, and atomicity, as it is known from thentransaction concept in database management systems. We describe thenmechanism incorporating both transactions and exceptions and present anvalidation technique allowing to assess the correctness of processnspecifications