Enterprise Identity Mapping (EIM) is an open architecture from IBM for helping an enterprise manage the multiple user registries and identities that enable a computer user to access multiple applications with a single sign-on. The architecture provides for a server that
client systems can access so that the users can access multiple applications, even those that are distributed in a network. Using EIM, authentication (which can use Kerberos or other authentication methods) and authorization processes can be located in separate places in a network. EIM is intended primarily for one-to-many mappings (single user, multiple identities). It can also support many-to-one mappings (multiple users, single identity), although this practice is not recommended. EIM can be integrated with directory services such as Active Directory and Novell Directory Services.