Modeling and Analyzing Multi-Agent Behaviors Using Predicate/Transition Nets

Abstract

How agents accomplish a goal task in a multi-agent system is usually specified by multiagent plans built from basic actions (e.g. operators) of which the agents are capable. The plan specification provides the agents with a shared mental model for how they are supposed to collaborate with each other to achieve the common goal. Making sure that the plans are reliable and fit for the purpose for which they are designed is a critical problem with this approach. To address this problem, this paper presents a formal approach to modeling and analyzing multi-agent behaviors using Predicate/Transition (PrT) nets, a high-level formalism of Petri nets. We model a multi-agent problem by representing agent capabilities as transitions in PrT nets. To analyze a multi-agent PrT model, we adapt the planning graphs as a compact structure for reachability analysis, which is coherent to the concurrent semantics. We also demonstrate that one can analyze whether parallel actions specified in multi-agent plans can be executed in parallel and whether the plans can achieve the goal by analyzing the dependency relations among the transitions in the PrT model.

An Approach of Quality of Service Assurance for Enterprise Cloud Computing (QoSAECC)

“…In the study of Xu, et al [4][5], they used a Predicate/Transition Petri Net (a kind of high-level Petri Net [6]) to simulate the agent design for the intended functions, security threats, and threat mitigations, and is used to verify and correct errors and deficiency of the design to the system security problems. Basically, it can be referred as an ISTA (Integration and System Test Automation) platform that generate test scripts based on the security model to simulate malicious behaviors, and then forwards test codes according to definition of user's MIN (Model-Implementation Mapping) to deal with security problem respectively.…”

A Tool for Automated Test Code Generation from High-Level Petri Nets

“…For example, if a goal marking is known to be reachable (or unreachable) from the initial marking but the reachability analysis reports a different result, then the PrT net models is not specified correctly (e.g., a precondition is missing). Reachability verification is conducted through the fast planning graph analysis adapted for the particular PrT nets in ISTA [8].…”

“…PrT nets in ISTA are a subset of traditional PrT nets [2] or colored Petri nets [3] 2 , where all weights in each formal sum of tokens or arc labels The formal definition of such PrT nets can be found in our prior work [7], [8].…”

Coordinating Agents Plans in Multi-Agent Systems Using Colored Petri Nets

“…[13] and [14] are two papers that deal with agent behavior coordination. Concerning Petri net based MAS modeling, there also exists research work emphasizing special modeling aspects [21], [22], [23] and [24], but with little emphasis on agent behavior coordination. A set of Petri net based moderators, each managing a single conversation, and a conversation server, which organizes moderators, are the moderator parts.…”

“…For example in [13], is introduced a moderator coordination model to handle agents communication from the organization level. For example, [22] emphasizes model verification to check whether a multi-agent plan is possible. In contrast, our work does not draw a clear boundary along conversations, but instead focuses on agent behavior from the view of an individual agent and from the global view of the whole MAS; this provides a powerful modular modeling.…”