A network management apparatus is configured to manage a network apparatuses and to store the work information and an augmented reality presenting apparatus. A tag is added to the network apparatuses and each of the network cables, and each of the tags is provided with a visible object that conforms to the tag information that includes an ID of a target to which the tag has been added. The network management apparatus transmits the guide information that includes the information that indicates the contents of a work for the work target based on the tag information of the work target or the tag shot image of the work target and the work information to the augmented reality presenting apparatus. The augmented reality presenting apparatus associates a guide that is based on the guide information with an input image from the shooting device, and displays the guide and the input image.