Page 236 - (ISC)² CISSP Certified Information Systems Security Professional Official Study Guide

protected against risks identified during the strategy development
phase. As with buildings and facilities, there are two main methods of

providing this protection.

Physically Hardening Systems You can protect systems against
the risks by introducing protective measures such as computer-safe
fire suppression systems and uninterruptible power supplies.

Alternative Systems You can also protect business functions by
introducing redundancy (either redundant components or completely
redundant systems/communications links that rely on different
facilities).

These same principles apply to whatever infrastructure components
serve your critical business processes—transportation systems,
electrical power grids, banking and financial systems, water supplies,
and so on.