Determining System Effectiveness Against Outsiders Using Assess

The determination of security system effectiveness against outsider threats using the Analytic System and Software for Evaluation of Safeguards and Security (ASSESS) is discussed. The measure of system effectiveness is P(W), the probability of system win. This paper first discusses a general approach to calculating P(W) for a single adversary path using a path event timeline, depicting detection and delay, and results from the Neutralization module of ASSESS. The approach allows the analyst to take account of the interplay between delay and protective force-adversary engagements as well as serial engagements. An alternate method is presented for finding P(W) for the most vulnerable path, the path minimizing P(W) among all paths. This estimate of P(W) combines the probability of interruption, P(I), the output of the ASSESS Outsider Module, with the probability of neutralization, P(N), the output of the ASSESS Neutralization module. The method should produce less conservative estimates of P(W) than previous approaches.