Name Identifier Mapping Protocol

The Name Identifier Mapping Protocol defines the request and response messages that one service provider can use to communicate with a second service provider to obtain the name identifier assigned to a principal federated in the name space of the second service provider. This would be used when a principal authenticated to one service provider requests access to a second service provider site with which it also has an identity federation relationship. The protocol allows the second service provider to communicate with the first service provider about the principal even though no identity federation for the principal exists between the two service providers.