A network facsimile apparatus is connected to a local area network, has a function of performing data transmission using electronic mail, and has a function of transmitting facsimile data to and receiving facsimile data from a facsimile apparatus using a predetermined facsimile transmission procedure via a public network. A circumferential axis along a circumferential direction of the ellipse or circle configuring the tooth top is longer in the non-drive-side half-tooth region than in the drive-side half-tooth region. The defocus regulation is executed after the detrack regulation is executed, in the state in which the servo control of the focusing and the servo control of the tracking are executed. The invention further describes a data transfer system, a device for utilizing application data, a memory device and a data transfer front end. In addition, incremental area removal method can be utilized to address resource utilization problem through a quality metric based on force directed placement transforms, such as a resource demand topological mapping.