TY - CONF AB - Many specifications include assumptions on the environment. If the environment satisfies the assumptions then a correct system reacts as intended. However, when the environment deviates from its expected behavior, a correct system can behave arbitrarily. We want to synthesize robust systems that degrade gracefully, i.e., a small number of environment failures should induce a small number of system failures. We define ratio games and show that an optimal robust system corresponds to the winning strategy of a ratio game, where the system minimizes the ratio of system errors to environment errors. We show that ratio games can be solved in pseudopolynomial time. AU - Bloem, Roderick AU - Greimel, Karin AU - Henzinger, Thomas A AU - Jobstmann, Barbara ID - 3835 TI - Synthesizing robust systems ER -