Identity management platform, service server, login system and federation method

The present invention relates to an identity management platform, a service server, a method for establishing identity combination, a united logging-on system and a method thereof. The identity management platform comprises an information receiving module, a combined managing module and an information transmitting module. The united logging-on system comprises an identity managing platform, a service server and an identity combination data base. The identity combining and logging-one method realizes united logging-on through combining the identity information of the user on identity management platform and the service server. The methods according to the invention can realize that the tedious identity authentication process is not required in service accessing after that the user establishes identity combination information. The tedious operation when the user accesses the service can be reduced. Furthermore the safety and reliability of important information such as user identity information, etc. can be guaranteed.