Identity Management System plays an important role in Cloud
Computing. A good Identity Management System should meet the diverse
security requirements from both service providers and users, improve
usability for users and protect the resources from unauthorized
access. The goal of the document is to document two kinds of level
of assurance, one for authentication and the other for attribute, to
provide users with a friendly experience through the use of
technologies based on the ABFAB architecture and specifications.
datatracker.ietf.org