In a traditional security model, assets have three attributes that require protection: Confidentiality, Integrity and Availability. This is known as the C-I-A model after the initial letters of this triad. However, in 1988 a cyber security expert called Donn Parker realised that there were other attributes that were important from a cyber perspective that the traditional model overlooked. So he added three more: Possession, Authenticity and Utility. Taken together these six attributes are now known as the Parkerian Hexad.
The diagram to the right shows the six security attributes in the inner blue ring and the method used to protect of each of these in the green outer ring. The green ring defends against attacks symbolised by the pink arrows. So, for example, ransomware is an attack on the availability attribute; access to data is denied until the ransom is paid. One defensive method against such an attack is good data backup discipline, combining both cloud-based storage and air-gapped hard drives.