N-GEN Communications Web-based Seminars ©NGCS

Seminar - An Overview of Communications Technologies

Module 2 - Data Communications Basics and Legacy Technologies                                                Slide 19 of 45 _________________                                                                                  __________

                                     Data Communications Equipment

                                                Datasets / Modems

                                                Line Drivers

                                                Multiplexers

                                                Routers

_________________                                                                                  __________

Data Communications Equipment provides the required functions to establish, maintain and terminate a connection, and provides signal conversion required for communications between data terminal equipment and the transmission medium.

Dataset / Modem - Allows digital messages to be transmitted over telephone lines. A dataset modulates and demodulates a digital signal. Asynchronous and synchronous datasets are available in the market.

Line Driver - Designed to transmit and receive a digital signal of suitable amplitude and shape to meet telephone company requirements for cross talk levels. Asynchronous and synchronous line drivers are available in the market.

Multiplexers - These are communications devices that allow a number of lower-speed terminals to share a high-speed line. Frequency Division Multiplexers (FDM), Time division multiplexers (TDM), Statistical Time Division Multiplexers (STDM) and Wave Division Multiplexers (WDM) are available in the marketplace.

Routers - A router is used to connect one or more LANs. Routers make the backbone network for the Internet. TCP / IP and Novell's IPX are the typical protocols used by the router Wide Area Networks.