What Every End User Should Know Q1. Controller-based modem designs use dedicated hardware to perform all the needed functions. Special silicon known as a modem chip set does the signal processing algorithms needed to modulate and demodulate your digital data onto the analog phone signal. The modem chip set also performs the system control functions. All external modems as well as many add-in boards and internal modems are of this DSP accelerated type.
Soft modems are the newest type of modem to come onto the PC market.
Here, both the control functions and the data pump functions are performed by the PC processor. In other words, with a soft modem, the entire modem function itself is executed in all-software and there is no DSP acceleration. Modem communications are performed reliably and quickly by subsystems designed for and dedicated to those specific tasks. On the other hand, controller-based modems also represent the highest hardware content and hence the highest incremental system costs. Traditional modems also used a separate microcontroller to perform system setup, call control, and other communications system.