What is an example of a physical security measure?

Access control systems, such as card readers, are a prominent example of a physical security measure because they are designed to restrict access to physical locations, ensuring that only authorized personnel can enter secured areas. These systems utilize physical devices to enforce security protocols, making them essential for safeguarding sensitive environments within an organization, particularly in the context of the Department of Defense.

In contrast, firewalls and data encryption belong to the realm of cybersecurity, focusing primarily on protecting digital information and networks rather than physical spaces. Intrusion detection systems, while they can monitor physical access and detect unauthorized actions, primarily serve as electronic tools that protect against threats to information systems rather than direct physical security control. Thus, access control systems represent a clear and direct method of physical security within the broader spectrum of security measures.