Security

Security is the degree of protection against danger, damage, loss, and crime. Security as a form of protection are structures and processes that provide or improve security as a condition. The Institute for Security and Open Methodologies (ISECOM) in the OSSTMM 3 defines security as "a form of protection where a separation is created between the assets and the threat". This includes but is not limited to the elimination of either the asset or the threat. Security as a national condition was defined in a United Nations study (1986) so that countries can develop and progress safely.

Security has to be compared to related concepts: safety, continuity, reliability. The key difference between security and reliability is that security must take into account the actions of people attempting to cause destruction.
Different scenarios also give rise to the context in which security is maintained:

• With respect to classified matter, the condition that prevents unauthorized persons from having access to official information that is safeguarded in the interests of national security.
• Measures taken by a military unit, an activity or installation to protect itself against all acts designed to, or which may, impair its effectiveness.

   Categorising security

  There is an immense literature on the analysis and categorisation of security. Part of the reason for this is that, in most security systems, the "weakest link in the chain" is the most important. The situation is asymmetric since the 'defender' must cover all points of attack while the attacker need only identify a single weak point upon which to concentrate.
  

   Types of security

  IT realm Application security Computing security Data security Information security Network security

  Physical realm Airport security Port security/Supply chain security Food security Home security Physical security School security Shopping centre security Infrastructure security

  Political Homeland security Human security International security National security Public security Monetary Financial security

• Aviation security is a combination of material and human resources and measures intended to counter unlawful interference with aviation.

• Operations Security (OPSEC) is a complement to other "traditional" security measures that evaluates the organization from an adversarial perspective.Security management in organizations In the corporate world, various aspects of security were historically addressed separately - notably by distinct and often noncommunicating departments for IT security, physical security, and fraud prevention. Today there is a greater recognition of the interconnected nature of security requirements, an approach variously known as holistic security, "all hazards" management, and other terms.
  Inciting factors in the convergence of security disciplines include the development of digital video surveillance technologies (see Professional video over IP) and the digitization and networking of physical control systems (see SCADA). Greater interdisciplinary cooperation is further evidenced by the February 2005 creation of the Alliance for Enterprise Security Risk Management, a joint venture including leading associations in security (ASIS), information security (ISSA, the Information Systems Security Association), and IT audit (ISACA, the Information Systems Audit and Control Association).
  In 2007 the International Organisation for Standardization (ISO) released ISO 28000 - Security Management Systems for the supply chain. Although the title supply chain is included, this Standard specifies the requirements for a security management system, including those aspects critical to security assurance for any organisation or enterprise wishing to management the security of the organisation and its activities. ISO 28000 is the foremost risk based security system and is suitable for managing both public and private regulatory security, customs and industry based security schemes and requirements.