Which of the following is an oft-cited cause of vulnerability of networks?

A. software monoculture

B. software diversification

C. single line of defense

D. multiple DMZ

E. None of the choices.

Explanation:

An oft-cited cause of vulnerability of networks is homogeneity or software monoculture. In particular, Microsoft Windows has such a large share of the market that concentrating on it will enable a cracker to subvert a large number of systems. Introducing inhomogeneity purely for the sake of robustness would however bring high costs in terms of training and maintenance.