Least suffering strategy in Distributed Real-Time Programming Language DROL

This paper describes a communication model for distributed real-time objects, called the Distributed Real-time Object (DRO) model. The main characteristic of this model is the notion of least suffering. Least suffering assures users to be notified network and computer faults within a required timing constraint and supports rapid recovery from them. Consequently, this notion allows users to construct real-time applications on widely distributed environments. The notion has been implemented in the programming language DROL which is an extension of C++. Through the design and implementation of a DROL programming environment on the ARTS kernel, we examine costs of least suffering in a network-wide object invocation. We also show the effectiveness of least suffering, through description of application programs and discussion of their behavior.