saravana,
Lightweight Third Party Authentication
Lightweight Third Party Authentication (LTPA) is intended for distributed, multiple application server and machine environments. LTPA supports forwardable credentials and single sign-on (SSO). LTPA can support security in a distributed environment through cryptography. This support permits LTPA to encrypt, digitally sign, and securely transmit authentication-related data, and later decrypt and verify the signature.
Application servers distributed in multiple nodes and cells can securely communicate using the LTPA protocol. It also provides the single sign-on (SSO) feature wherein a user is required to authenticate only once in a domain name system (DNS) domain and can access resources in other WebSphere® Application Server cells without getting prompted. The realm names on each system in the DNS domain are case sensitive and must match identically.
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