Confidentiality, integrity and availability (CIA triad)
The CIA triad, consisting of confidentiality, integrity, and availability, serves as a foundational model for developing cybersecurity policies across various organizations. Confidentiality focuses on restricting unauthorized access to sensitive information, ensuring that only authorized individuals can view or manipulate data. Integrity is concerned with maintaining the accuracy and trustworthiness of data, protecting it from unauthorized changes while allowing for correction of errors made by authorized users. Availability guarantees that authorized users have reliable access to information when needed, which relies on the proper maintenance of the underlying technical infrastructure.
Historically, each component of the CIA triad evolved over time, beginning with discussions about confidentiality in the mid-1970s and culminating in the unification of the concepts in the late 1990s. The model has gained prominence with the rise of Big Data and the Internet of Things (IoT), reflecting the growing complexities of modern cybersecurity challenges. Additionally, the CIA triad can be expanded to include elements like authenticity, which verifies the legitimacy of the data's origin, and non-repudiation, which ensures accountability for data actions. Other complementary frameworks, such as the Distributed, Immutable, and Ephemeral (DIE) model, further enhance the strategies for managing information security in today’s interconnected environment.
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Confidentiality, integrity and availability (CIA triad)
The CIA triad of confidentiality, integrity, and availability is a widely used model for the development of cybersecurity policies within various organizations. In the context of the CIA triad, confidentiality refers to the set of rules that limits access to information, integrity is the assurance that the information in question is accurate and trustworthy, and availability is a guarantee that authorized individuals will have reliable access to the information. As a concept, the CIA triad is aimed at encouraging people to be mindful of the different aspects of information technology (IT) security. When security experts design cybersecurity protocols for an organization, they examine potential threats and evaluate the impact that these threats are likely to have on the confidentiality, integrity, and availability of the organization’s critical information. In some cases, the CIA triad is alternatively known as the AIC triad so it is not confused with the Central Intelligence Agency (CIA).
Overview
The CIA triad is a three-pronged model for the development of cybersecurity policies that various entities use to protect their IT systems and data. Each prong of the model—confidentiality, integrity, and availability—is a crucial element of strong cybersecurity. The confidentiality component of the CIA triad is about preventing unauthorized parties from accessing sensitive private information through methods such as hacking. In any well-organized cybersecurity system, confidentiality is achieved by defining and enforcing separate levels of access to information. This often means organizing information into different categories based on who needs access to certain data and how sensitive that data is. In other words, information is separated depending on how much damage would likely be incurred in the event of a confidentiality breach. The integrity component of the triad is concerned with ensuring the consistency, accuracy, and trustworthiness of data at all times. This means protecting data from modification or deletion by unauthorized parties. It also means ensuring that mistakes made by authorized users can be easily remedied without leaving any lasting damage. The availability component of the CIA triad is focused on ensuring that information is easily and consistently accessible to authorized parties. This requires the careful maintenance of the hardware, technical infrastructure, and systems used to store and display data.
Rather than being created all at once, the CIA triad gradually evolved into its complete form as each individual component developed over time. The historic roots of the CIA triad stretch back to 1976, when the concept of confidentiality as it applies to computer science was likely first formalized in a US Air Force study. The concept of integrity was similarly first described in a paper published in 1987 that examined the need for data correctness in commercial computing applications tied to accounting records. Availability first started to be discussed after an early piece of malware called the Morris worm knocked out a large part of the fledgling Internet in 1988. It appears that the three components of the CIA triad were first joined as a single unit in the late 1990s. The CIA triad continues to play a major role in the development of cybersecurity measures, especially as Big Data and the Internet of Things (IoT) have come to play an increasingly large role in the modern online world.
A different construct of the CIA triad adds the additional elements of “Authenticity” and “Non-repudiation.” Authenticity implies the originator of an IT action is known and is legitimate. Non-repudiation provides for accountability. Its premise is that a person responsible for conducting an IT action should be identiable. These additional elements, in addition to the existing triad, are essential in establishing confidence that data is protected and reliable.
Another complementary model to CIA, one that operates in tandem and not as a replacement for CIA, has been termed Distributed, Immutable, and Ephemeral (DIE). Distributed seeks to minimize dependency on critical nodes so that if one or more becomes unavailable, serious impacts to the entire system do not develop. Immutable refers to designing replaceability in key system areas. Ephemeral allows for assets to be disposed of if a security breach were to emerge.
Bibliography
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