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NEAR EAST UNIVERSITY FACULTY OF ENGINEERING DEPARTMENT OF COMPUTER ENGINEERINGCOM 318 DATA COMMUNICATIONS LECTURE NOTESPrepared by Dr. Tayseer AlshanablehTMPDF Editor
Nicosia-2007 COM 318-Ch.I-IV 07/08 Fall TABLE OF CONTENTSCH. 1: INTRODUCTION TO DATA COMMUNICATIONS CH. 2: DATA TRANSMISSION & SIGNALS CH. 3: TRANSMISSION MEDIA CH. 4: ENCODING, MODULATING & TRANSMISSION CODES CH. 5: TRANSMISSION OF DIGITAL DATA: INTERFACES & MODEMS CH. 6: MULTIPLEXING CH. 7: ERROR DETECTION AND CORRECTIONTMPDF Editor
1 COM 318-Ch.I-IV 07/08 Fall CHAPTER 1 INTRODUCTION TO DATA COMMUNICATIONS? -COMPUTER NETWORKInterconnected collection of autonomous computers that are able to exchange information. No master/slave relationship between computers in the network. DATA COMMUNICATIONSTransmission of signals in a reliable and efficient matter. ? ? COMMUNICATION MODEL (SYSTEM)The purpose of a communications system is to exchange data between two entities. Source: entity that generates data; eg. a person who speaks into the phone, or a computer sending data to the modem. Transmitter: a device to transform/encode the signal generated by the source. – the transformed signal is actually sent over the transmission system. eg. a modem transforms digital data to analog signal that can be handled by the telephone network. ? Transmission System (Channel): medium that allows the transfer of a signal from one point to another. eg. a telephone network for a computer/modem. ? Receiver: a device to decode the received signal for handling by destination device. eg. A modem converts the received analog data back to digital for the use by the computer. ? Destination: entity that finally uses the data. eg. Computer on other end of a receiving modem. Data Communications Data communications is the transfer of information that is in digital form, before it enters the communication system. – Basic Elements of a Communication System Signal s(t)
Transmitter…