Amit K. Chopra

Amit K. Chopra, Samuel H. Christie, Munindar P. Singh

Communication protocols are central to engineering decentralized multiagent systems. Modern protocol languages are typically formal and address aspects of decentralization, such as asynchrony. However, modern languages differ in important ways in their basic abstractions and operational assumptions. This diversity makes a comparative evaluation of protocol languages a challenging task. We contribute a rich evaluation of modern protocol languages based on diverse approaches. Among the selected languages, Scribble is based on session types; Trace-C and Trace-F on trace expressions; HAPN on hierarchical state machines, and BSPL on information causality. Our contribution is four-fold. One, we contribute important criteria for evaluating protocol languages. Two, for each criterion, we compare the languages on the basis of whether they are able to specify elementary protocols that go to the heart of the criterion. Three, for each language, we map our findings to a canonical architecture style for multiagent systems, highlighting where the languages depart from the architecture. Four, we identify a few design principles for protocol languages as guidance for future research.

Thomas C. King, Akın Günay, Amit K. Chopra et al.

The notion of commitment is widely studied as a high-level abstraction for modeling multiagent interaction. An important challenge is supporting flexible decentralized enactments of commitment specifications. In this paper, we combine recent advances on specifying commitments and information protocols. Specifically, we contribute Tosca, a technique for automatically synthesizing information protocols from commitment specifications. Our main result is that the synthesized protocols support commitment alignment, which is the idea that agents must make compatible inferences about their commitments despite decentralization.

Amit K. Chopra

The traditional understanding of stakeholders requirements is that they express desirable relationships among phenomena in the relevant environment. Historically, software engineering research has tended to focus more on the problems of modeling requirements and deriving specifications given requirements, and much less on the meaning of a requirement itself. I introduce new concepts that elucidate the meaning of requirements, namely, the designated set and the falsifiability of requirements. By relying on these concepts, I (i) show that the adaptive requirements approaches, which constitute a lively and growing field in RE, are fundamentally flawed, (ii) give a sufficient characterization of vague requirements, and (iii) make the connection between requirements modeling and the Zave and Jackson sense of engineering. I support my claims with examples and an extensive discussion of the related literature. Finally, I show how adaptation can be framed in terms of Zave and Jackson's ontology.