Since the introduction of Alternating-time Temporal Logic (ATL), many logics
have been proposed to reason about different strategic capabilities of the
agents of a system. In particular, some logics have been designed to reason
about the uniform memoryless strategies of such agents. These strategies are
the ones the agents can effectively play by only looking at what they observe
from the current state. ATL_ir can be seen as the core logic to reason about
such uniform strategies. Nevertheless, its model-checking problem is difficult
(it requires a polynomial number of calls to an NP oracle), and practical
algorithms to solve it appeared only recently.
This paper proposes a technique for model checking uniform memoryless
strategies. Existing techniques build the strategies from the states of
interest, such as the initial states, through a forward traversal of the
system. On the other hand, the proposed approach builds the winning strategies
from the target states through a backward traversal, making sure that only
uniform strategies are explored. Nevertheless, building the strategies from the
ground up limits its applicability to constrained reachability objectives only.
This paper describes the approach in details and compares it experimentally
with existing approaches implemented into a BDD-based framework. These
experiments show that the technique is competitive on the cases it can handle.Comment: In Proceedings GandALF 2017, arXiv:1709.0176