A formal framework for agent interaction semantics

ABSTRACT

Although informative, the semantic definition proposed for the most standard agent communication language (FIPA ACL 1997) is complicated and contentious, while published interaction protocols (IPs) tend to be ambiguous, incomplete, and unverified with respect to message semantics. To clarify and help rectify these problems, this paper proposes an integrated framework based on Propositional Dynamic Logic and Belief and Intention modalities (called the PDL-BI language). Specifically, we provide an axiomatisation of PDL-BI and for an agent's propositional attitudes (beliefs and intentions) and social attitudes (such as sincerity and trustworthiness). Then we suggest a revised and simpler core semantics for many of the FIPA ACL speech acts, which, in turn, lead to the specification of the semantics of IPs. As a case study, we specify the semantics of the contract net protocol (CNP) in PDL-BI, which allows to prove that the CNP terminates.

REFERENCES

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INDEX TERMS

Primary Classification:
  I. Computing Methodologies
  I.2 ARTIFICIAL INTELLIGENCE
        I.2.11 Distributed Artificial Intelligence

General Terms:
Languages, Theory, Verification

Keywords:
belief, intention ACL, interaction state, protocol, semantics