Direct Inward Dialing Support. This function is offered by telephone companies with the goal that ATC clients could connect all range of company numbers to one or several lines. The aim is to give a personal number to every employee without having to connect it to a separate phone line. Thus, all telephone traffic can be divided and controlled more efficiently.
Heswick is a company that works for a number of years in Telecommunications developing hardware and software solutions dedicated to telephony services management.