Account linking 1-- built on variant two with the Person Registry. The Registry remembers all of the accounts that a person can use (eg OpenID, institution issued credentials, etc). The user's history and permissions are associated with all of the login accounts. (Perhaps some privileges require higher LoA authN?)
Account linking 2-- Sara has been accessing the public portions of SonnetBlast, a Bamboo workspace, based on an authentication to her FaceBook account. Six months later Sara starts a research plan that requires advanced features of SonnetBlast only accessible via federated login using her Wattsamatta U. userid. When Sara logs into SonnetBlast via the federated login for the first time, Bamboo, seeing this as a new user, prompts Sara to create a new account or to use an existing account. If she indicates that she has an existing account, she is prompted to login via an IdP she has used to access that account. The action identifies the existing account and her new login is then associated with that account.
Account linking 3-- Assistant Professor Kohlrabi has a Bamboo identity created under his Garden State College issued userid. Budget cuts to the university threaten to snowball into layoffs in the assistant professoriate. Based on Bamboo FAQ advice, He decides to link his Google account to his Bamboo identity as a precaution against losing his Bamboo portfolio in the event his university credentials are yanked as part of a termination of appointment.
He authenticates to the Bamboo account linking site with his institutional identity. He is invited to chose a social identity provider, clicks on a link that takes him to a Google login popup. After successfully authenticating, he is informed that his Bamboo account is now accessible via his google account credentials, regardless of the status of his Garden State ID. However, because the rights to access certain online journals and Bamboo data files depend on faculty status, he will not have access to those resources when logged in with his Google account. If he leaves GSU and takes an appointment at Trenton State, he will regain access to the data files and resources once he links his Trenton State identity via Account Linking Scenario 2.
Account linking 4-- Professor Jessica Postlethwaite holds joint appointments at Harvard and MIT in nanosemiotics. She is a senior partner in The Semiotics of Nanotechnology Bamboo Workspace. To bring together her data files from both MIT and Harvard, she uses the account linking service to link her Harvard and MIT identities, thereby consolidating them under a single Bamboo Person ID. Note that specific access rights are associated with particular identities, so there are some MIT materials that she cannot access when logged in via Harvard credentials.