Solving the Workflow Satisfiability Problem using General Purpose Solvers

Karapetyan, Daniel; Gutin, Gregory

Abstract

The workflow satisfiability problem (WSP) is a well-studied problem in access control seeking allocation of authorised users to every step of the workflow, subject to workflow specification constraints. It was noticed that the number k of steps is typically small compared to the number of users in the real-world instances of WSP; therefore k is considered as the parameter in WSP parametrised complexity research. While WSP in general was shown to be W[1]-hard, WSP restricted to a special case of user-independent (UI) constraints is fixed-parameter tractable (FPT). However, restriction to the UI constraints might be impractical. To efficiently handle non-UI constraints, we introduce the notion of branching factor of a constraint. As long as the branching factors of the constraints are relatively small and the number of non-UI constraints is reasonable, WSP can be solved in FPT time. Extending the results from Karapetyan et al. (2019), we demonstrate that general-purpose solvers are capable of achieving FPT-like performance on WSP with arbitrary constraints when used with appropriate formulations. This enables one to tackle most of practical WSP instances. While important on its own, we hope that this result will also motivate researchers to look for FPT-aware formulations of other FPT problems.

Citation

Karapetyan, D., & Gutin, G. (2023). Solving the Workflow Satisfiability Problem using General Purpose Solvers. IEEE Transactions on Dependable and Secure Computing, 20(6), 4474 - 4485. https://doi.org/10.1109/tdsc.2022.3227241

• Journal Article Type: Article
• Acceptance Date: Nov 18, 2022
• Online Publication Date: Dec 7, 2022
• Publication Date: Nov 13, 2023
• Deposit Date: Mar 12, 2025
• Publicly Available Date: Mar 13, 2025
• Journal: IEEE Transactions on Dependable and Secure Computing
• Print ISSN: 1545-5971
• Electronic ISSN: 1941-0018
• Publisher: Institute of Electrical and Electronics Engineers
• Peer Reviewed: Peer Reviewed
• Volume: 20
• Issue: 6
• Pages: 4474 - 4485
• DOI: https://doi.org/10.1109/tdsc.2022.3227241
• Keywords: Electrical and Electronic Engineering
• Public URL: https://nottingham-repository.worktribe.com/output/14602090
• Publisher URL: https://www.computer.org/csdl/journal/tq/2023/06/09973378/1IUAQvQFqmI
• Related Public URLs: https://arxiv.org/abs/2105.03273