Patent ID: 8090948

Claim:
An image formation system comprising a terminal device, an image formation apparatus and a server device, said terminal device including an inputting portion inputting user identification information, and a sender sending a plurality of print jobs to said image forming apparatus, each print job of the plurality including user identification information associated therewith, said image formation apparatus including a receiver receiving a plurality of print jobs and said user identification information associated therewith, a requester requesting authentication of said server device for a first print job received from the plurality of print jobs if a certificate with matching user identification information is not found in said image formation apparatus, said authentication indicating if said user identification information associated with said first job is one from a user permitted to use said image formation apparatus, an image forming portion, upon receipt of the certificate issued by said server device indicating that the user is permitted to use said image formation apparatus, forming an image based on said first print job, a holder holding said certificate including said user identification information in said image formation apparatus during a validity period defined for said certificate, and a simplified authentication portion determining if user identification information associated with at least a second print job from the plurality of print jobs received by said image formation apparatus corresponds to said user identification information of the certificate held by said holder, said image forming portion performing an image formation process for the at least a second print job when said simplified authentication portion determines that the certificate exists with said user identification information, without requesting authentication of the server, said server device including an authentication portion performing authentication as to whether a user is one permitted to use said image formation apparatus based on the user identification information for which the authentication was requested by said requester, and an issuer issuing a certificate indicating that a user is permitted to use said image formation apparatus by said authentication portion and sending the certificate to said image formation apparatus.