Author(s):

Chatterjee, Krishnendu; Henzinger, Thomas A; Jobstmann, Barbara

Title: 
Environment assumptions for synthesis

Title Series: 
LNCS

Affiliation 

Abstract: 
The synthesis problem asks to construct a reactive finitestate system from an omegaregular specification. Initial specifications are often unrealizable, which means that there is no system that implements the specification. A common reason for unrealizability is that assumptions on the environment of the system are incomplete. We study the problem of correcting an unrealizable specification phi by computing an environment assumption psi such that the new specification psi > phi is realizable. Our aim is to construct an assumption psi that constrains only the environment and is as weak as possible. We present a twostep algorithm for computing assumptions. The algorithm operates on the game graph that is used to answer the realizability question. First, we compute a safety assumption that removes a minimal set of environment edges from the graph. Second, we compute a liveness assumption that puts fairness conditions on some of the remaining environment edges. We show that the problem of finding a minimal set of fair edges is computationally hard, and we use probabilistic games to compute a locally minimal fairness assumption.

Conference Title:

CONCUR: Concurrency Theory

Volume: 
5201

Conference Dates:

August 1922, 2008

Conference Location:

Toronto, Canada

ISBN:

9783959770170

Publisher:

Schloss Dagstuhl  LeibnizZentrum für Informatik

Location:

Berlin, Heidelberg

Date Published:

20080730

Start Page: 
147

End Page:

161

DOI: 
10.1007/9783540853619_14

Open access: 
no 