Secure state
Encyclopedia
A secure state is Information System
security
term to describe where entities in an computer system are divided into subjects and objects, and it can be formally proven that each state transition preserves security by moving from one secure state to another secure state. Thereby it can be inductively
proven that the system is secure. As defined in the Bell–LaPadula model, the secure state is built on the concept of a state machine with a set of allowable states in a system. The transition from one state to another state is defined by transition function
s.
A system state is defined to be "secure" if the only permitted access modes of subjects to objects are in accordance with a security policy
. To determine whether a specific access mode is allowed, the clearance of a subject is compared to the classification of the object to determine if the subject is authorized for the specific access mode. The clearance/classification scheme is expressed in terms of a lattice of access control
rules.
Information system
An information system - or application landscape - is any combination of information technology and people's activities that support operations, management, and decision making. In a very broad sense, the term information system is frequently used to refer to the interaction between people,...
security
Computer security
Computer security is a branch of computer technology known as information security as applied to computers and networks. The objective of computer security includes protection of information and property from theft, corruption, or natural disaster, while allowing the information and property to...
term to describe where entities in an computer system are divided into subjects and objects, and it can be formally proven that each state transition preserves security by moving from one secure state to another secure state. Thereby it can be inductively
Mathematical induction
Mathematical induction is a method of mathematical proof typically used to establish that a given statement is true of all natural numbers...
proven that the system is secure. As defined in the Bell–LaPadula model, the secure state is built on the concept of a state machine with a set of allowable states in a system. The transition from one state to another state is defined by transition function
Transition function
In mathematics, a transition function has several different meanings:* In topology, a transition function is a homeomorphism from one coordinate chart to another...
s.
A system state is defined to be "secure" if the only permitted access modes of subjects to objects are in accordance with a security policy
Security policy
Security policy is a definition of what it means to be secure for a system, organization or other entity. For an organization, it addresses the constraints on behavior of its members as well as constraints imposed on adversaries by mechanisms such as doors, locks, keys and walls...
. To determine whether a specific access mode is allowed, the clearance of a subject is compared to the classification of the object to determine if the subject is authorized for the specific access mode. The clearance/classification scheme is expressed in terms of a lattice of access control
Access control
Access control refers to exerting control over who can interact with a resource. Often but not always, this involves an authority, who does the controlling. The resource can be a given building, group of buildings, or computer-based information system...
rules.
See also
- Bell–LaPadula model
- TCSEC - The Orange Book