[Minoli80] D. Minoli, Cost Implications of Survivability of Terrestrial Networks under Malicious Failure, IEEE Transactions on Communications 28, no. 9 (September 1980):1668--1674. [This paper describes the difference in cost if we attempt to defend against intentional disruption of communications networks as opposed to the cost of defending against random failures. The costs of redundancy increase almost exponentially for malicious attacks, which demonstrates clearly the inadequacy of statistical methods for providing availability measures under malicious attack.]