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Related to security: Security Essentials


1. something given or pledged to secure the fulfilment of a promise or obligation
2. a person who undertakes to fulfil another person's obligation
3. the protection of data to ensure that only authorized personnel have access to computer files


(computer science)
The existence and enforcement of techniques which restrict access to data, and the conditions under which data may be obtained.
The ability of an electric power system to suitably respond to disturbances arising within that system, including both local and widespread disturbances and the loss of major generation and transmission facilities.
Measures taken by a command to protect itself from espionage, observation, sabotage, annoyance, or surprise.
A condition which results from the establishment and maintenance of protective measures which ensure a state of inviolability from hostile acts or influences.
Protection of supplies or supply establishments against enemy attack, fire, theft, and sabotage.


A combination of measures and human and material resource intended to safeguard international civil aviation against acts of unlawful interference (ICAO).


Protection against unauthorized access to, or alteration of, information and system resources including CPUs, storage devices and programs.

Security includes:

* confidentiality - preventing unauthorized access; integrity - preventing or detecting unauthorized modification of information.

* authentication - determining whether a user is who they claim to be.

* access control - ensuring that users can access the resources, and only the resources, that they are authorised to.

* nonrepudiation - proof that a message came from a certain source.

* availability - ensuring that a system is operational and accessible to authorised users despite hardware or software failures or attack.

* privacy - allowing people to know and control how information is collected about them and how it is used.

Security can also be considered in the following terms:

* physical security - who can touch the system to operate or modify it, protection against the physical environment - heat, earthquake, etc.

* operational/procedural security - who is authorised to do or responsible for doing what and when, who can authorise others to do what and who has to report what to who.

* personnel security - hiring employees, background screening, training, security briefings, monitoring and handling departures.

* System security - User access and authentication controls, assignment of privilege, maintaining file and filesystem integrity, backup, monitoring processes, log-keeping, and auditing.

* network security - protecting network and telecommunications equipment, protecting network servers and transmissions, combatting eavesdropping, controlling access from untrusted networks, firewalls, and intrusion detection.

Encryption is one important technique used to improve data security.

OWASP is the free and open application security community.


An umbrella term for the protection of electronic data and networks. In the IT world, security comprises authorization (who has access?), authentication (is this "really" the authorized user?), encryption (scrambling data for privacy), malware protection (avoiding destructive infiltration), as well as backup and disaster recovery (assurance against failure). See security suite, computer security, information security, security audit, security protocol, access control, authentication, cryptography, malware, backup and disaster recovery.
References in periodicals archive ?
In the case of computer systems, administrative functions are the most sensitive, because they typically enjoy access to all data and security measures.
"When an insurance company issues a security, its treatment by rating agencies and regulatory bodies can impact the composition of the insurer's balance sheet and the level of capital and surplus it reports," said Edward Easop, vice president of rating criteria for A.M.
* alleges that the defendant misrepresented or omitted a material fact or employed a manipulative device or contrivance in connection with the purchase, sale or holding of the equity or other security.
To protect their employees, confidential information and physical assets properly, the majority of New York tenants install security systems in their office suites.
OSI Systems' Rapiscan Systems division has received a Transportation Security Administration contract to implement a baggage and parcel inspection product line.
In a statement issued in preparation for the hearing, Burton stated: "We have already begun the process of working with our friends by launching the Partnership for Prosperity (P4P) and the Security and Prosperity Partnership of North America (SPP), but more needs to be done to stem the tide of illegal aliens into the United States in the short-term, as well as to pave the way towards a long-term, coordinated and legal immigration plan for our Hem# sphere." (Emphasis added.)
Large-scale security assistance programs are subject to constant and justifiable scrutiny and oversight from DoD security assistance program organizations, Services, the Office of the Secretary of Defense, the Office of Management and Budget, and interagency stakeholders.
Charlie Garten, the former chief information officer for the Poway Unified School District in southern California, says his district's struggles with Wi-Fi security began as early as 2002.
DevPartner SecurityChecker is a security assessment tool that accelerates the development of secure ASP.NET applications.
Under the terms of the policy, employees who are disabled for more than a year must apply for Social Security benefits; in July 2002 Mrs.
Community colleges have responded to the Department of Homeland Security offer by repositioning themselves as the training ground for "first responders"--the police officers, firefighters, emergency workers and health professionals expected to arrive first on the scene after a terrorist attack.