Asymmetric warfare is the application of dissimilar strategies, tactics, capabilities and approaches used to circumvent or negate an opponent's strengths while exploiting his weaknesses.
Auditing is the information gathering and analysis of assets to ensure such things as policy compliance and security from vulnerabilities.
Authentication is the process of confirming the correctness of the claimed identity.
Authenticity is the validity and conformance of the original information.
Authorization is the approval, permission, or empowerment for someone or something to do something.
One network or series of networks that are all under one administrative control. An autonomous system is also sometimes referred to as a routing domain. For the purposes of Internet routing, an autonomous system is assigned a globally unique number by a registrar, called an Autonomous System Number (ASN).
Availability is the need to ensure that the business purpose of the system can be met and that it is accessible to those who need to use it.
A backdoor is a tool installed after a compromise to give an attacker easier access to the compromised system around any security mechanisms that are in place.