Ability to prove the occurrence of a claimed event or action and its originating entities.
Source: ISO/IEC 27000:2014, Information technology — Security techniques — Information security management systems — Overview and vocabulary, Third Edition, January 2014. Global Standards
A property achieved through cryptographic methods to protect against an individual or entity falsely denying having performed a particular action related to data.
Extended Definition: Provides the capability to determine whether a given individual took a particular action such as creating information, sending a message, approving information, and receiving a message.
Adapted from: CNSSI 4009; From: NIST SP 800-53 Rev 4.
Source: NICCS™ Portal Cybersecurity Lexicon, National Initiative for Cybersecurity Careers and Studies (https://niccs.us-cert.gov/glossary) as of 11 November 2015, Global Standards