A cassette loading device includes a dust protection mechanism having a dustproof lid member provided on the cassette, and the dustproof lid member is closed when an access to the recording medium is judged to be unnecessary even in the course of holding the cassette loaded in the recording andor reproducing apparatus. A connection of the housing to the first part of the folding top of andor a connection the controller member to the second part is constructed as a movable connection. A method and system for generating a transposed output signal from an input signal using a transposition factor T is described. If difference between the lowest lower bound and the lowest upper bound is less than a threshold, the power flow is outputted based on the lowest lower bound and the lowest upper bound. The module then causes the virtual switch to route the network packet to the selected vNIC and software port.