ABSTRACT
The co-evolution of offence and defence takes place globally, largely because knowledge about cyberspace, in much the same sense that mathematics is, is global. The relationship of measure to countermeasure suggests that negative feedback plays a large role in the ecology of cyberspace. In almost every other military domain, a dyadic contest can be characterized as one military entity versus another. At the high end, cyberspace intrusions are often one-offs, almost by definition, and any domain characterized by coupling between measures and countermeasures inevitably evolves too fast to be the subject of formal modelling. Hackers generally breach systems by finding paths that exist through a combination of stolen credentials and software vulnerabilities. So, the contest in cyberspace has two near-orthogonal vectors: offence versus defence, and state versus state. The competition in cyberspace has many such characteristics; in other words, one side’s defences contend with their offences and vice versa.
