Core Concepts
The paper introduces a powerful hyper logical framework called generalized HyperLTL with stuttering and contexts (GHyperLTLS+C) that unifies known asynchronous extensions of HyperLTL and the KLTL logic for specifying and analyzing hyperproperties in the linear-time setting. It identifies a meaningful decidable fragment of GHyperLTLS+C, called simple GHyperLTLS+C, that is more expressive than HyperLTL and known fragments of asynchronous HyperLTL, and can express important properties like diagnosability, information-flow security, and bounded termination.
Abstract
The paper introduces a novel logical framework called generalized HyperLTL with stuttering and contexts (GHyperLTLS+C) that unifies known asynchronous extensions of HyperLTL and the KLTL logic for specifying and analyzing hyperproperties in the linear-time setting.
Key highlights:
GHyperLTLS+C extends HyperLTLS and HyperLTLC with past temporal modalities and general trace quantification, providing a powerful mechanism to compare histories of computations at distinct time points and relate an unbounded number of traces.
The paper identifies a meaningful decidable fragment of GHyperLTLS+C, called simple GHyperLTLS+C, that is more expressive than HyperLTL and known fragments of asynchronous HyperLTL.
Simple GHyperLTLS+C can express important properties like diagnosability, information-flow security (both synchronous and asynchronous), and bounded termination.
The paper shows that simple GHyperLTLS+C subsumes KLTL under the synchronous semantics and the one-agent fragment of KLTL under the asynchronous semantics.
The (fair) model checking problem for simple GHyperLTLS+C is proven to be decidable.