What is a Web-SSO ?
A SSO (Single Sign On) is a system that is used to share authentications between many applications. User logs in only one time and is never prompted when he tries to access to another application. Kerberos (used in Active Directory) for example is an SSO mechanism. The problem with these systems is that in addition to their heaviness, they apply only to internal networks and to relatively homogeneous machines.The Web-SSO is the bearing of this principle restricted with the Web applications. The user is thus authenticated with the first access to a protected Web application and the authentications are propagated when it changes application. The large advantage is whereas the system is usable on Internet without pre-necessary on the stations customers (they just have to accept session cookies). For example, when a user reaches a Google letter-box, it is not authenticated if it reaches the groups management application or any other Google application.
