About
A principal is an identity assigned to a user or group as a result of authentication.
It represents then a user or group.
As part of a successful authentication, principals are signed and stored in a Weblogic - Login Module (Control Flag and authentication flow) for future use.
Each principal stored in the same subject represents a separate aspect of the same user’s identity, much like cards in a person’s wallet.
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JAAS
Whether the client is an application, applet, Enterprise JavaBean (EJB), or servlet that requires authentication, WebLogic Server uses the Java Authentication and Authorization Service (JAAS) classes to reliably and securely authenticate to the client. JAAS implements a Java version of the Pluggable Authentication Module (PAM) framework, which permits applications to remain independent from underlying authentication technologies.