BOTTOM: Masters, I am to discourse wonders: butask me not what; for if I tell you, I am no trueAthenian. I will tell you every thing, right as itfell out.
|--A Midsummer Night's Dream, IV, ii, 30–33.|
Although access controls can constrain the rights of a user, they cannot constrain the flow of information about a system. In particular, when a system has a security policy regulating information flow, the system must ensure that the information flows do not violate the constraints of the policy. Both compile-time mechanisms and runtime mechanisms support the checking of information flows. Several systems implementing these mechanisms demonstrate their effectiveness.
Information flow policies define ...