The nature and attribute of security

The nature of security is the matter of trust.
The design of all security solutions are based on trust. We must trust something and have some basic assumptions then security solutions can be established; if we deny everything, the security solutions will be like water without a source, wood without a root, cannot be designed and cannot be completed.
Grasping the degree of trust condition and making it appropriate is the difficulty of designing security solution and the artistic charm of security science.
The three elements of security are the basic elements of security; they are Confidentiality, Integrity, and Availability.
Confidentiality requires that data content be protected from disclosure; encryption is a common means of achieving confidentiality requirements.
Integrity requires the protection of data content is complete, not tampered with. A common technique for ensuring integrity is a digital signature.
Availability requires that resources are available whenever necessary.