The process of proving that a person or other agent has been correctly identified, or that a message is received as transmitted.
Authentication supports the principle of accountability .
Monitoring network transmissions to gather information. This is a form of passive attack on data confidentiality and includes unauthorized interception of messages. Gathering unprotected passwords is often the primary reason for mounting an eavesdropping attack on a network. For example, integrity means that the data or message is not destroyed or corrupted, and that systems operate correctly. When confidentiality is violated but the state of the system is not affected, an attack is passive .