User Authentication

Types of User Authentication:

                   I.            Authentication helps to establish trust by identifying a particular user on a system.

                 II.            Authentication is just a mechanism to establish trust and authenticate a user by traditional approach of user id and password.

              III.            Authentication tokens add randomness to the password based mechanism and make it very secure. This mechanism requires the user to process the tokens.

              IV.            Certificate based authentication has a modern communication mechanism based on PKI technology. Smart card is an example of this mechanism which facilitates cryptographic operation inside the card.

                V.            Biometric authentication is based on human biological characteristic.

              VI.            Kerberos is a single sign on approach which can only implemented on many real life systems.

Authentication:

It is a technique where the entity being authenticated knows a secret and the authenticator knows the value that is derived from the secret.

Password:

A password is a string of alphabets, numbers and special characters which is supposed to be known only to a single entity that is being authenticated.

                 i.)            Clear Text password:

This is the simplest password based authentication in which all users have some user id and initial passwords. The user changes the password time to time for security reason and password is stored in clear text in user database against the user id on the server, This authentication mechanism have the following steps –

a.     Prompt for user id and password.

b.     User enters user id and password.

c.      User id and password validated.

d.     Authentication result.

e.     Inform user accordingly.