Personnel security, to protect the individual or group of individuals who are authorized to access the organization and its operations
Operations security, to protect the details of a particular operation or series of
activities
Communications security, to protect communications media, technology, and content
Network security, to protect networking components, connections, and contents
Information security, to protect the confidentiality, integrity and availability of information assets, whether in storage, processing, or transmission. It is achieved via the
application of policy, education, training and awareness, and technology