Digital telephony systems

Digital telephony is the use of digital technology in the provision of telephone services and systems.The old analog telephone system was almost entirely replaced by digital systems since1960s. This system improved voice services as well as the speed of data transfer over telephone lines.  Almost all calls are controlled  by digital system at present, but sometimes it is restricted to cases in which the last mile is digital. The last mile is the final leg of delivering connectivity from a communications provider to a customer.

cheap software