Open Modeling in Multi-stakeholder Distributed Systems: Research and Tool Challenges

Abstract

The design and use of multi-stakeholder distributed systems (MSDSs — in which nodes are designed or operated by distinct stakeholders having limited knowledge and possibly conflicting goals) challenge our traditional conceptions of requirements engineering and system validation in two ways. First, global inconsistency among high-level requirements forces us to focus on the personalized and time sensitive requirements of a single stakeholder, rather than the more traditional global, time-invariant requirements. Second, any given stakeholder will typically lack detailed knowledge of the behaviors of nodes not under his control; such knowledge is necessary to validating requirements conformance. OpenModel [1] is a research effort whose aim is to address this ”ignorance problem” through open, standardized behavioral modeling. In OpenModel, each node of an MSDS such as the Internet email system or a network of web services provides via http (or through a central registry) a behavioral model expressed in terms of shared domain-specific function/object theories. By assembling these models appropriately, tools based upon techniques like scenario simulation, animation, coverage measurement, theorem proving, and model checking can support a wide range of automated software engineering activities: personalized requirements engineering, validation, on-line help, node design, configuration, and evolution.