1. A method for converting digital electrical data into modulated optical streams, said method comprising inputting into an optical modulator N bits of digital data in parallel, N being larger than 1; using a digital to digital converter to map a set of N input values corresponding to said N bits of digital data to a set of M output values where M is larger than N and where the input and output values are not identical; using the M output values to drive at least M electrodes, enabled to modulate at least an optical input optical stream to provide at least a modulated output optical stream.