Once an incident is detected, people intervene.
Examples include:
most methods for disaster recovery (which require human
involvement during the recovery process),
updating of known-virus checkers for new viruses, and
recovering from most denial of service attacks.
Complexity: Reactive human responses are limited to situations in which
real-time (within a small number of computer cycles) response is not
required, and is limited by the skills of the defenders.
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