Robert Graham, Technology betrays everyone
The task of information security is to protect information. This is done by regulating the access and modification of data and information systems. There are thee main aspects of information security: confidentiality, integrity and availability. They are also known as the CIA triad.
Confidentiality (Est: konfidentsiaalsus) means that only authorized people can access a given information. Data is inaccessible for all others.
Integrity (Est: terviklus) preserves data accuracy and completeness throughout its life-cycle. For example, integrity assures that the data is not changed while in transit. It can also provide non-repudiation, which gives a proof for the origin of the data.
Availability (Est: käideldavus) means that data should be accessible (for authorized people) when needed. For information systems, it means that the servers must be up and network communication working. Data availability assures that the former is true even in case of power outage, hardware failures or when system is under (denial of service) attack.