Security can be defined as state of freedom from a danger, risk or attack. Information security can be defined as the task of guarding information which is processed by a server, stored on a storage device, and transmitted over a network like Local Area Network or the public Internet. Information security means protecting information and information systems from unauthorized access, use, disclosure, disruption, modification or destruction
Introduction to AAA
AAA stands for Authentication, Authorization and Accounting. AAA are a set of primary concepts that aid in understanding computer and network security as well as access control. These concepts are used daily to protect property, data, and systems from intentional or even unintentional damage. AAA is used to support the Confidentiality, Integrity, and Availability (CIA) security concept.
Confidentiality: The term confidentiality means that the data which is confidential should remain confidential. In other words, confidentiality means secret should stay secret.
Integrity: The term integrity means that the data being worked with is the correct data, which is not tampered or altered.
Availability: The term availability means that the data you need should always be available to you.
Authentication provides a way of identifying a user, typically requiring a Userid/Password combo before granting a session. Authentication process controls access by requiring valid user credentials. After the Authentication process is completed successfully, a user must be given authorization (permission) for carrying out tasks within the server. Authorization is the process that determines whether the user has the authority to carry out a specific task. Authorization controls access to the resources after the user has been authenticated. The last one is Accounting. Accounting keeps track of the activities the user has performed in the server.