Bell-LaPadula Security Model Main Rules

1. Simple Security Rule - A subject cannot read data within an object that resides at a higher security level. This is known as "No read up".

2. * - Property Rule - A subject cannot write to an object at a lower security level. This is known as "No write down".

3. Strong Star Property Rule - For a subject to be able to read and write to an object, the subject's clearance and the object's classification must be equal.