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Writing up.

Note
The US Central Intelligence Agency, or any other government clandestine organization, operates intelligence collection using the write up concept. Agents go out, collect small bits of intelligence data, and then send that data back to headquarters. Only at headquarters, once the data has been assembled and examined in its entirety, will the true usefulness and value of the data come forth. The sensitivity of the final object will be much higher than the level of access of any of the agents.

State Machine Model

A state machine model is a mathematical model that groups all possible system occurrences, called states. Every possible state of a system is evaluated, showing all possible interactions between subjects and objects. If every state is proven to be secure, the system is proven to be secure.

State machines are used to model real-world software when the identified state must be documented along with how it transitions from one state to another. For example, in object-oriented programming, a state machine model may be used to model and test how an object moves from an inactive state to an active state readily accepting input and providing output.

Bell-LaPadula Model

The Bell-LaPadula model was originally developed for the US Department of Defense. It is focused on maintaining the confidentiality of objects. Protecting confidentiality means not allowing users at a lower security level to access objects at a higher security level. Bell-LaPadula operates by observing two rules: the Simple Security Property and the * Security Property.