Specification and automatic verification of trust-based multi-agent systems

Abstract

We present a new logic-based framework for modeling and automatically verifying trust in Multi-Agent Systems (MASs). We start by refining TCTL, a temporal logic of trust that extends the Computation Tree Logic (CTL) to enable reasoning about trust with preconditions. A new vector-based version of interpreted systems is defined to capture the trust relationship between the interacting parties. We introduce a set of reasoning postulates along with formal proofs to support our logic. Moreover, we present new symbolic model checking algorithms to formally and automatically verify the system under consideration against some desirable properties expressed using the proposed logic. We fully implemented our proposed algorithms as a model checker tool called MCMAS-T on top of the MCMAS model checker for MASs along with its new input language VISPL (Vector-extended ISPL). We evaluated the tool and reported experimental results using a real-life scenario in the healthcare field.

Formalizing Group and Propagated Trust in Multi-Agent Systems

“…Although TCTL has been presented with interesting reasoning postulates [Drawel et al, 2017;Drawel et al, 2020], a deep analysis of this logic reveals a major paradox resulted from the underlying assumption that complies with the first postulate in [Singh, 2011] stating that "when the content holds, the trust in this content is completed and is, therefore, no longer active". Indeed, enforcing the condition ¬ϕ to be satisfied in the current state s for the trust to take place yields the following paradoxical postulate:…”

“…Following this work, a number of trust models have been put forward and several proposals investigated trust propagation [Jamali and Ester, 2010;Chakraborty and Karform, 2012]. On the other hand, the latter deals with how one agent in the system can trust that another agent behaves and will perform an action in a certain way [Singh, 2011;Primiero and Raimondi, 2014;Primiero, 2016;Liu and Lorini, 2017;Drawel et al, 2020].…”

“…Moreover, some proposals have abstracted from the cognitive stance and presented trust as a direct modality. In [Drawel et al, 2020], a new branching temporal logic of preconditional trust, which extends the Computation Tree Logic (CTL) is introduced along with its model checking technique. [Singh, 2011] provided a formal semantics for trust with various logical postulates used to reason about trust from an architectural perspective.…”

“…A branching temporal logic extending CTL has been introduced to reason about trust and time in MASs [Drawel et al, 2017;Drawel et al, 2020]. This logic, called TCTL provides an interesting framework to reason about individual trust.…”

Knowledge-Based Verification of Concatenative Programming Patterns Inspired by Natural Language for Resource-Constrained Embedded Devices

“…Rule base systems to model new DSLs using sets of if–then rules can be also found in the literature [ 39 ]. Novel logic languages intended for formal specification and verification have been introduced to abstract, express and check desirable properties, e.g., trust, in distributed systems [ 40 ], or to specify typical embedded and Cyber-Physical System functionalities like sensing, actuation, and communication [ 41 ]. In the latter case, statistical, instead of exhaustive, model checking techniques are adopted to avoid state space explosion [ 42 ].…”