federation
The establishment of some or all of business agreements, cryptographic trust and user identifiers or attributes across security and policy domains to enable more seamless business interaction.
As web services promise to enable integration between business partners through loose coupling at the application and messaging layer, federation does so at the identity management layer, insulating each domain from the details of the others' authentication and authorization. Key to this loose coupling at the identity management layer are standardized mechanisms and formats for the communication of identity information between the domains. SAML is one such standard.