Joseph Pamula Sushil Jajodia Paul Ammann Vipin Swarup A weakest-adversary security metric for network configuration security analysis. 31-38 2006 QoP http://doi.acm.org/10.1145/1179494.1179502 conf/ccs/2006qop db/conf/ccs/qop2006.html#PamulaJAS06