What does configuration management control over a system life cycle?

Configuration management specifically focuses on the control of changes to configuration items throughout a system's life cycle. This process ensures that all aspects of a system, including hardware, software, and documentation, are properly managed and tracked over time. By controlling changes, configuration management helps maintain the integrity and performance of systems while minimizing the risk of errors that can arise from unauthorized or poorly managed modifications.

This discipline involves identifying configuration items, documenting their characteristics, and managing changes in a structured manner. For instance, when updates or repairs are made to software applications, configuration management procedures ensure that such changes are systematically documented and implemented, maintaining compliance with established policies and standards.

In contrast, the other options do not accurately reflect the primary function of configuration management. The use of hardware components, storage of user data, and network security protocols each relate to different aspects of system management but do not encapsulate the essence of what configuration management controls and monitors. Therefore, focusing on the changes to configuration items is key to understanding configuration management's role in lifecycle management.