Outline
     Data Communications
     Networking
     OSI Reference Model
     TCP/IP Protocol Architecture
     Networking Components
     More detailed contents are covered by 
        COMP4510: Foundations of Information 
        Technology
                             COMP4690, by Dr Xiaowen Chu,  HKBU     2
     Data Communications
     Data communications deals with the 
        transmission of signals in a reliable and 
        efficient manner. Topics covered include 
        signal transmission, transmission media, 
        signal encoding, interfacing, data link control, 
        and multiplexing.
                             COMP4690, by Dr Xiaowen Chu,  HKBU     3
      A Communications Model
       Purpose of Communications
           Exchange of data (information) between entities
       Key elements
         •   Source
             − Generates data to be transmitted
         •   Transmitter
             − Converts data into transmittable signals
         •   Transmission System
             − Carries data
         •   Receiver
             − Converts received signal into data
         •   Destination
             − Takes incoming data
                                    COMP4690, by Dr Xiaowen Chu,  HKBU              4
     A Communications Model
                             COMP4690, by Dr Xiaowen Chu,  HKBU     5
     Networking
     Point to point communication is not usually 
        practical
         Devices are too far apart
         Large set of devices would need impractical 
          number of connections
     Solution is a communications network
         Local Area Network (LAN)
         Metropolitan Area Network (MAN)
         Wide Area Network (WAN)
                             COMP4690, by Dr Xiaowen Chu,  HKBU     6