Source : Free On-Line Dictionary of Computing

SoftModem
     
        The integration of {modem} controller and {data pump}
        {algorithm}s into a single {RAM}-based {DSP} hardware
        architecture.  These integrated algorithms are stored on the
        computer's hard disk, from which they are downloaded into the
        DSP board's random access memory (RAM).  This downloading, or
        "booting" process of the PC-installed software algorithms
        occurs as part of the computer's power-up initialisation
        process in less than 100 milliseconds, making it transparent
        to the user.
     
        [Digicom Modem FAQ version 2.03].