Date Added: Aug 2011
A trust metric is described for a user to ensure the authenticity of another user who is not known to system entities in an open environment. On the basis of the metric, an identity federation framework is proposed for propagating an authentication assertion for an unknown user across system entities. The unknown user directly interacts with an authenticating user with the support of an entity mediating the authentication. By use of the proposed framework, an entity receiving an authentication assertion can derive and evaluate the trust value of its corresponding user in a quantitative fashion to flexibly control his or her access.