More detail provided in the detailed use case scenarios. Each scenario contains a short description of the scenario, a UML sequence diagram illustrating the action in the scenario, a description of each step, and a list of requirements that are related to the scenario. In this use case, a Web user authenticates with a Web site. The Web user then uses a secured resource at another Web site, without directly authenticating to that Web site. Web user authenticates to the source Web site.
Web user uses a secured resource at the destination Web site.
This scenario is an elaboration of the Single Sign-on use case. In this model, the destination Web site pulls authentication information from the source Web site based on references or tokens provided by the Web user. Single Sign-on, Pull Model. Web user authenticates with source Web site. Web user requests link to destination Web site.