Which aspect of security focuses on preventing unauthorized access to facilities?

The aspect of security that focuses on preventing unauthorized access to facilities is physical security. This area encompasses various measures designed to protect the physical premises and assets of an organization from unauthorized access, theft, or damage. Physical security can include the use of locks, surveillance cameras, security guards, access control systems, and barriers, all aimed at safeguarding the facility and its occupants.

In contrast, network security primarily deals with protecting the integrity and usability of networks and data during transmission, protecting against intrusions and unauthorized access to networks. Application security focuses on ensuring that software applications are secure from threats and vulnerabilities that could be exploited. Data security involves protecting data from unauthorized access, disclosure, alteration, and destruction, but it does not specifically address physical environments or facility access.