A conversion server stores therein a combination of client information indicating the type of a client terminal and content information that is requested to be sent from the client terminal. Furthermore, the conversion server stores therein server information indicating a conversion server responsible for the format of content in such a manner that the server information is associated with the combination of the client information and the content information. If the conversion server receives, from the client terminal, a send request for content, the conversion server distinguishes between the client information on the client terminal and the content information on the content requested to be sent. The conversion server notifies a conversion server indicated by the server information associated with the combination of the distinguished client information and the distinguished content information of the distinguished client information and the distinguished content information.