Patent ID: 8176538

Claim:
An information processing system, comprising: an information distribution server; a client apparatus; and a service providing server that provides a service to a user of the client apparatus, wherein the information distribution server comprises: a user authentication information memory that stores user authentication information of the user, the user authentication information for authenticating the user on the client apparatus; a receiving section that receives authentication information from the service providing server, the authentication information for authenticating the user on the service providing server; and an authentication proxy information distributing section that distributes to the client apparatus authentication proxy information comprising the user authentication information and the authentication information, the authentication proxy information for authenticating a proxy on behalf of the user on the service providing server; and wherein the client apparatus comprises: a user authentication section that authenticates the user using the distributed user authentication information, and an authentication proxy section that, in response to the user requesting access to the service providing server, executes proxy authentication as the proxy to authenticate the user on behalf of the user on the service providing server using the authentication information included in the authentication proxy information distributed by the authentication proxy information distributing section.