A graphical code reader includes an imager that provides image data corresponding to a two-dimensional image of a graphical code. The priority scheme is based on an amount of preallocated bandwidth unused by channel unit ports. A part of diffraction light generated by the pinhole is irradiated to the mirror to be measured; the light reflected by the mirror to be measured is reflected by a frame of the pinhole and generate a diffraction fringe along with another part of the diffraction wavefront of the pinhole. Accounting services can take account of the usage and charges associated with the underlying services to provide accounting and billing on a per-request basis or per customer-provider pair for a billing period. The elongated member is configured to transmit control motions from the robotic system to an end effector.