1. A method of performing knowledge-based authentication (KBA), the method comprising: obtaining a set of user facts from a personal information management (PIM) server that is under the control of an organization, each user fact of the set of user facts including a reference to a user identifier of a user that is a member of the organization; generating a set of KBA questions from the set of user facts; and providing selected KBA questions of the set of KBA questions to a person that has submitted a request to access resources of the organization, the request including the user identifier; wherein generating the set of KBA questions from the set of user facts includes: for each KBA question of the set of KBA questions: producing a generation score that is based on the facts of the set of facts from which the KBA question was generated, removing the KBA question from the set of KBA questions when the generation score is less than a threshold generation score, and keeping the KBA question in the set of KBA questions when the generation score is greater than the threshold generation score.
1. A method of performing knowledge-based authentication (KBA), the method comprising: obtaining a set of user facts from a personal information management (PIM) server that is under the control of an organization, each user fact of the set of user facts including a reference to a user identifier of a user that is a member of the organization; generating a set of KBA questions from the set of user facts; and providing selected KBA questions of the set of KBA questions to a person that has submitted a request to access resources of the organization, the request including the user identifier; wherein generating the set of KBA questions from the set of user facts includes: for each KBA question of the set of KBA questions: producing a generation score that is based on the facts of the set of facts from which the KBA question was generated, removing the KBA question from the set of KBA questions when the generation score is less than a threshold generation score, and keeping the KBA question in the set of KBA questions when the generation score is greater than the threshold generation score. 7. A method as in claim 1 , wherein providing the selected KBA questions of the set of KBA questions includes: obtaining a set of policies from a policy server; and selecting the selected KBA questions from the set of KBA questions based on the policy.