Maximizing survivability of vulnerable weighted voting system

The weighted voting system (WVS) studied consists of N units that each provide a binary decision (0 or 1) or abstain from voting. Each unit has its own individual weight. System output is 1 if the cumulative weight of all 1-opting units is at least a pre-specified fraction τ of the cumulative weight of all non-abstaining units. Otherwise system output is 0. For a system consisting of voting units (VUs) with given reliability characteristics one can maximize the entire system reliability by choosing proper unit weights and threshold values τ. When a system operates in battle conditions or is affected by a corrosive medium or other hostile environment, its survivability (the ability to tolerate intentional attacks or accidental failures or errors) is becoming especially important. One of the ways to enhance voting system survivability is to separate its VUs. We formulate the problem of maximizing survivability of WVS by proper choice of unit weights and system threshold value and by unit separation. An algorithm for solving the problem is based on using a universal generating function technique for evaluating system survivability. A genetic algorithm is used as the optimization tool. Examples are presented.