Cloud Platforms require secure authentication and authorization. There are various methods of authentication for different type of applications and users, such as: Password authentication, Biometric authentication, Smart card authentication, Finger print authentication, etc.
Remote users can be authenticated via a Remote Authentication Dial-In user Service (RADIUS) or the Internet Authentication Service (IAS).

Single Sign-On (SSO) is a feature that allows a user to use one password (or smart card) to authenticate to multiple servers on a network without reentering credentials. This is an obvious convenience for users, who don’t have to remember multiple passwords or keep going through the authentication process over and over to access different resources.