A method and system for authenticating a user. A first server of at least two servers receive input authentication information from the user. The first server ascertains that the user is authorized to access a federated computing environment that comprises at least two servers, which includes the first server determining that the received input authentication information conforms to at least one rule of an authentication policy of a second server having a highest relative priority among servers of the at least two servers whose authentication policy's at least one rule, in an authentication policy table within the first server, is conformed to by the received input authentication information.