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Computer Security Policy
A computer security policy defines the goals and elements of an organization's computer systems. The definition can be highly formal or informal. Security policies are enforced by organizational policies or security mechanisms. A technical implementation defines whether a computer system is ''secure'' or ''insecure''. These formal policy models can be categorized into the core security principles of confidentiality, integrity, and availability. For example, the Bell–LaPadula model is a ''confidentiality policy model'', whereas the Biba model is an ''integrity policy model''. Formal description If a system is regarded as a finite-state automaton with a set of transitions (operations) that change the system's state, then a ''security policy'' can be seen as a statement that partitions these states into authorized and unauthorized ones. Given this simple definition, one can define a ''secure system'' as one that starts in an authorized state and will never enter an unauthorized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Computer Security Model
{{short description, Plan for specifying and enforcing security policies A computer security model is a scheme for specifying and enforcing security policies. A security model may be founded upon a formal model of access rights, a model of computation, a model of distributed computing, or no particular theoretical grounding at all. A computer security model is implemented through a computer security policy. For a more complete list of available articles on specific security models, see :Computer security models. Selected topics * Access control list (ACL) * Attribute-based access control (ABAC) * Bell–LaPadula model * Biba model * Brewer and Nash model * Capability-based security * Clark-Wilson model * Context-based access control (CBAC) * Graham-Denning model * Harrison-Ruzzo-Ullman (HRU) * High-water mark (computer security) * Lattice-based access control In computer security, lattice-based access control (LBAC) is a complex access control model based on the inte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Bell–LaPadula Model
The Bell–LaPadula model (BLP) is a state-machine model used for enforcing access control in government and military applications. It was developed by David Elliott Bell, and Leonard J. LaPadula, subsequent to strong guidance from Roger R. Schell, to formalize the U.S. Department of Defense (DoD) multilevel security (MLS) policy. The model is a formal state transition model of computer security policy that describes a set of access control rules which use security labels on objects and clearances for subjects. Security labels range from the most sensitive (e.g., "Top Secret"), down to the least sensitive (e.g., "Unclassified" or "Public"). Features The Bell–LaPadula model focuses on data confidentiality and controlled access to classified information, in contrast to the Biba Integrity Model which describes rules for the protection of data integrity. In this formal model, the entities in an information system are divided into subjects and objects. The notion of a "secu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Biba Model
The Biba Model or Biba Integrity Model developed by Kenneth J. Biba in 1975, is a formal state transition system of computer security policy describing a set of access control rules designed to ensure data integrity. Data and subjects are grouped into ordered levels of integrity. The model is designed so that subjects may not corrupt data in a level ranked higher than the subject, or be corrupted by data from a lower level than the subject. In general the model was developed to address integrity as the core principle, which is the direct inverse of the Bell–LaPadula model which focuses on confidentiality. Features In general, preservation of data ''integrity'' has three goals: * Prevent data modification by unauthorized parties * Prevent unauthorized data modification by authorized parties * Maintain internal and external consistency (i.e. data reflects the real world) This security model is directed toward data ''integrity'' (rather than ''confidentiality'') and is characte ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Finite-state Automaton
A finite-state machine (FSM) or finite-state automaton (FSA, plural: ''automata''), finite automaton, or simply a state machine, is a mathematical model of computation. It is an abstract machine that can be in exactly one of a finite number of ''states'' at any given time. The FSM can change from one state to another in response to some inputs; the change from one state to another is called a ''transition''. An FSM is defined by a list of its states, its initial state, and the inputs that trigger each transition. Finite-state machines are of two types— deterministic finite-state machines and non-deterministic finite-state machines. For any non-deterministic finite-state machine, an equivalent deterministic one can be constructed. The behavior of state machines can be observed in many devices in modern society that perform a predetermined sequence of actions depending on a sequence of events with which they are presented. Simple examples are: vending machines, which dispens ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Chinese Wall
A Chinese wall or ethical wall is an information barrier protocol within an organization designed to prevent exchange of information or communication that could lead to conflicts of interest. For example, a Chinese wall may be established to separate people who make investments from those who are privy to confidential information that could improperly influence the investment decisions. Firms are generally required by law to safeguard insider information and ensure that improper trading does not occur. Etymology Bryan Garner's ''Dictionary of Modern Legal Usage'' states that the metaphor title "derives ''of course'' from the Great Wall of China",, italics added although an alternative explanation links the idea to the screen walls of Chinese internal architecture. The term was popularized in the United States following the stock market crash of 1929, when the U.S. government legislated information separation between investment bankers and brokerage firms, in order to limit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Brewer And Nash Model
The Brewer and Nash model was constructed to provide information security access controls that can change dynamically. This security model, also known as the Chinese wall model, was designed to provide controls that mitigate conflict of interest in commercial organizations and is built upon an information flow model. In the Brewer and Nash model, no information can flow between the subjects and objects in a way that would create a conflict of interest. This model is commonly used by consulting and accounting firms. For example, once a consultant accesses data belonging to Acme Ltd, a consulting client, they may no longer access data to any of Acme's competitors. In this model, the same consulting firm can have clients that are competing with Acme Ltd while advising Acme Ltd. This model uses the principle of data isolation within each conflict class of data to keep users out of potential conflict of interest situations. Because company relationships change all the time, dynamic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Type Enforcement
The concept of type enforcement (TE), in the field of information technology, is an access control mechanism for regulating access in computer systems. Implementing TE gives priority to mandatory access control (MAC) over discretionary access control (DAC). Access clearance is first given to a subject (e.g. process) accessing objects (e.g. files, records, messages) based on rules defined in an attached security context. A security context in a domain is defined by a domain security policy. In the Linux security module (Linux Security Modules, LSM) in SELinux, the security context is an extended attribute. Type enforcement implementation is a prerequisite for MAC, and a first step before multilevel security (MLS) or its replacement multi categories security (MCS). It is a complement of role-based access control (RBAC). Control Type enforcement implies fine-grained control over the operating system, not only to have control over process execution, but also over domain transition o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Anti-virus
Antivirus software (abbreviated to AV software), also known as anti-malware, is a computer program used to prevent, detect, and remove malware. Antivirus software was originally developed to detect and remove computer viruses, hence the name. However, with the proliferation of other malware, antivirus software started to protect against other computer threats. Some products also include protection from malicious URLs, spam, and phishing. History 1971–1980 period (pre-antivirus days) The first known computer virus appeared in 1971 and was dubbed the " Creeper virus". This computer virus infected Digital Equipment Corporation's ( DEC) PDP-10 mainframe computers running the TENEX operating system.From the first email to the first YouTube video: a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
CIA Triad
Information security is the practice of protecting information by mitigating information risks. It is part of information risk management. It typically involves preventing or reducing the probability of unauthorized or inappropriate access to data or the unlawful use, disclosure, disruption, deletion, corruption, modification, inspection, recording, or devaluation of information. It also involves actions intended to reduce the adverse impacts of such incidents. Protected information may take any form, e.g., electronic or physical, tangible (e.g., paperwork), or intangible (e.g., knowledge). Information security's primary focus is the balanced protection of data confidentiality, integrity, and availability (also known as the 'CIA' triad) while maintaining a focus on efficient policy implementation, all without hampering organization productivity. This is largely achieved through a structured risk management process. To standardize this discipline, academics and professionals col ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
Firewall (computing)
In computing, a firewall is a network security system that monitors and controls incoming and outgoing network traffic based on configurable security rules. A firewall typically establishes a barrier between a trusted network and an untrusted network, such as the Internet or between several VLANs. Firewalls can be categorized as network-based or host-based. History The term '' firewall'' originally referred to a wall to confine a fire within a line of adjacent buildings. Later uses refer to similar structures, such as the metal sheet separating the engine compartment of a vehicle or aircraft from the passenger compartment. The term was applied in the 1980s to network technology that emerged when the Internet was fairly new in terms of its global use and connectivity. The predecessors to firewalls for network security were routers used in the 1980s. Because they already segregated networks, routers could filter packets crossing them. Before it was used in real-life comput ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] [Amazon] |
