The invention provides a computer system which is related with a Web server for providing a Web site over the Internet. This overcomes the problem in current common rail injection systems of the adapted valve position of the volumetric flow control valve often being subject to error, for instance because the valve position is controlled as a function of the rail pressure only using a one-dimensional adaptation characteristic field. The optical pre-processor includes either an optical polarization section having a polarization rotator and an optical polarizer, a phase modulation section that includes a phase modulator and a dispersion element and a clock recovery circuit, or an amplitude modulation section that includes an amplitude modulator clock recovery circuit and a spectral shaping filter.