CIA Triad

The CIA triad is a well-known model in information security development. It is applied in various situations to identify problems or weaknesses and to establish security solutions. It is an industry standard that information systems professionals should be familiar with.

What is the CIA Triad?

The CIA triad refers to an information security model made up of the three main components: confidentiality, integrity and availability. Each component represents a fundamental objective of information security. In order to avoid confusion, the CIA triad is sometimes referred to as the AIC triad, or PAIN, which stands for privacy, availability/authentication, integrity and non-repudiation.

The three components of the triad are discussed below:

  1. Confidentiality: This component is closely linked with privacy. This means that data are only available to the appropriate parties, which may be parties that require access to the data or parties that are trusted. Data that have been kept confidential means that they have not been compromised by other parties; confidential data are not disclosed to people who do not require them or who should not have access to them. Ensuring confidentiality means that information is organized in terms of who ought to have access as well as its sensitivity. A breach of confidentiality may take place through different means, for instance hacking or social engineering.
  2. Integrity: Data integrity refers to the certainty that the data are not tampered with during or after submission. It is the certainty that the data will not be modified or destroyed by unauthorized parties. This means there are two points during the transmission process during which the integrity could be compromised: during the upload or transmission of data; during the storage of the document in the database or collection.
  3. Availability: This means that the information is available when it is needed. In order for a system to demonstrate availability, it must have properly functioning computing systems, security controls and communication channels. The most available systems are accessible at all times and have safeguards against power outages, natural disasters, hardware failures and systems upgrades.

Availability is a major challenge in collaborative environments as such environments must be stable and continually maintained. Such systems must also allow users to access required information with little waiting time. Redundant systems may be in place to offer a high level of fail-over. The concept of availability can also refer to the usability of a system.

Information security refers to the preservation of integrity and secrecy when information is stored or transmitted. Information security breaches occur when information is accessed by unauthorized individuals or parties. Breaches may be the result of actions of hackers, intelligence agencies, criminals, competitors, employees or others. In addition, individuals who value and wish to preserve their privacy are interested in information security.

CIA Triad & Privacy

The fundamental security principles represented in the CIA triad ensure that both the data and the information system that processes the data are protected. The model takes into account different controls, physical security, technical security and human actions. Confidentiality, integrity and availability form three points of the information security triangle. The closer a system moves towards an apex, the further it is from the other two points. Thus, the CIA triad offers a useful model for the evaluation of technological choices. Put together, the triad preserves and protects sensitive information, whether it is personal or proprietary.


Information security professionals must establish the issues around the CIA triad, enforce controls, develop preventative procedures and monitor data stored on those systems. The CIA triad ensures that protection takes place on three levels: the physical, personal and organizational. Professionals may apply the following to ensure high standards of information security:

  • Cryptography: this is the way in which raw data are encrypted as a scrambled form before they are transmitted or stored. They are then decrypted into the original form when an authorized individual needs to access the data. This is the primary tool of information security.
  • Mechanisms for data integrity, such as digital signatures and hash algorithms. These mechanisms for identity authentication are important to ensure that only authorized people have access to the information.
  • High availability protocols, redundant network architectures and systems hardware designed to ensure reliability and robustness.

Blind Spots

Although the CIA triad is a fundamental model for information security, it also focuses on a limited view of IT security that is centered on information. While the priority is to protect the information and ensure that data resources are available, the CIA model does not address prevention of an unauthorized person from using the system’s hardware resources.

Another issue is the information security professionals will concentrate on the “confidentiality” part of the triad, essentially ignoring the other components of a balanced security approach. For instance, when the “accessibility” component of the triad is neglected, this could mean severe disruptions to communications, costing millions and significantly impacting an industry. Thus, it is necessary for security professionals to contribute skills and knowledge during the purchasing and selection process for an organization’s communications network.

It is crucial to ensure that the CIA triad is applied in a balanced fashion. While all three elements are important, different elements of the triad will take priority depending on the industry and organization. During the security evaluations process of an information project, each of the three elements is marked relative to each other. In many cases, the objective is to find a balance between the three elements, not to achieve the highest possible score on the evaluation.

There are certain rules, such as if the confidentiality and integrity of the system increases, the availability score should decrease. This may be completely acceptable, depending on the context of the system. In this way, the CIA triad can be broad and flexible, meaning that it can be relevant to and implemented in any organization. The CIA triad could be applied to a user requesting use of their personal laptop at their workplace, or the introduction of a new password policy in a company.

Many information security professionals have also advocated expanding the CIA model to include the element of accountability. This may include logging and auditing of investigations and the ways that data is collected before and during a particular incident. Accountability may include non-repudiation, which proves the party that performs an activity, the scope of the action and when the action took place.


This article introduces the model of the CIA triad for designing and assessing information systems. It provides a discussion of the three main components of the triad: confidentiality, integrity and availability. This triad has been the basis of the information security industry for over twenty years. The article goes on to discuss the application of the CIA triad, for instance in cryptography, authentication and network architectures. Finally, the article provides some points of critique and suggested improvements for the CIA triad.

Foundations Exam Preparation

In preparation for the Certification Foundation exam, a privacy professional should be comfortable with topics related to this post, including:

  • Elements of effective privacy management (I.G.b.)
  • Information security management (II.C.b.)

6 comments to CIA Triad

  • Imran Khan


    This is very helpful to understand the basics…!

  • Chandrika Bandaranayake

    thanks very helpfull

  • jbush

    I’m having trouble with availability and accessibility. It seems like something must be accessible to be available, right?

  • hannah

    Yes, they’re very closely linked. Availability refers to the idea that your application and the data within it will be accessible to the intended audience when the access is required. Likewise, it will not be accessible to those who don’t require the access. (Concept of least privilege)

    Hope this helps!

  • Thomas

    Thanks alot. i like the way you define each components of the CIA traid

  • hilda

    thanks so much I like the way you define it

Leave a Reply




You can use these HTML tags

<a href="" title=""> <abbr title=""> <acronym title=""> <b> <blockquote cite=""> <cite> <code> <del datetime=""> <em> <i> <q cite=""> <strike> <strong>