Conditions of saddle point existence in multilevel information security systems

Abstract

When planning the unified information security systems calculation of optimal resource amount needed for defence and their allocation between the objects, which differ in amount of information, vulnerability or attack probability, are important problems. Search for solution gets more complex over uncertainty of attackers actions. Under the circumstances appropriate is considered solution that match with saddle point of objective function, which express one of security system indicators – part of lost information, benefits of an investment in information security, investment efficiency – depending on correlation of attack and defence resources. Carried out calculations enable to analyse conditions of saddle point existence in one- and multilevel systems, which differ in quantity of objects and obstacles that defend them. It is demonstrated that saddle point exists in certain intervals of values Z=X/Y; intervals are determined by form of objects dynamic vulnerability and distribution of information between the objects.