Chapter 3 - Physical layer. In this chapter, the following content will be discussed: Circuits, digital transmission of digital data, analog transmission of digital data, digital transmission of analog data, analog/digital modems, multiplexing. | Business Data Communications and Networking 8th Edition Jerry Fitzgerald and Alan Dennis John Wiley & Sons, Inc Prof. M. Ulema Manhattan College Computer Information Systems 3 - Copyright 2005 John Wiley & Sons, Inc Chapter 3 Physical Layer 3 - Copyright 2005 John Wiley & Sons, Inc Outline Circuits Configuration, Data Flow, Communication Media Digital Transmission of Digital Data Coding, Transmission Modes, Analog Transmission of Digital Data Modulation, Voice Circuit Capacity, Digital Transmission of Analog Data Pulse Amplitude Modulation, Voice Data Transmission, Instant Messenger Transmitting Voice Data Analog/Digital Modems Multiplexing FDM, TDM, STDM, WDM, Inverse Multiplexing, DSL 3 - Copyright 2005 John Wiley & Sons, Inc Physical Layer - Overview Includes network hardware and circuits Network circuits: physical media (., cables) and special purposes devices (., routers and hubs). Types of Circuits Physical circuits connect devices & include actual wires . | Business Data Communications and Networking 8th Edition Jerry Fitzgerald and Alan Dennis John Wiley & Sons, Inc Prof. M. Ulema Manhattan College Computer Information Systems 3 - Copyright 2005 John Wiley & Sons, Inc Chapter 3 Physical Layer 3 - Copyright 2005 John Wiley & Sons, Inc Outline Circuits Configuration, Data Flow, Communication Media Digital Transmission of Digital Data Coding, Transmission Modes, Analog Transmission of Digital Data Modulation, Voice Circuit Capacity, Digital Transmission of Analog Data Pulse Amplitude Modulation, Voice Data Transmission, Instant Messenger Transmitting Voice Data Analog/Digital Modems Multiplexing FDM, TDM, STDM, WDM, Inverse Multiplexing, DSL 3 - Copyright 2005 John Wiley & Sons, Inc Physical Layer - Overview Includes network hardware and circuits Network circuits: physical media (., cables) and special purposes devices (., routers and hubs). Types of Circuits Physical circuits connect devices & include actual wires such as twisted pair wires Logical circuits refer to the transmission characteristics of the circuit, such as a T-1 connection refers to Mbps Can be the same or different. For example, in multiplexing, one wire carries several logical circuits Physical Layer Network Layer Data Link Layer 3 - Copyright 2005 John Wiley & Sons, Inc Types of Data Transmitted Analog data Produced by telephones Sound waves, which vary continuously over time Can take on any value in a wide range of possibilities Digital data Produced by computers, in binary form, represented as a series of ones and zeros Can take on only 0 ad 1 3 - Copyright 2005 John Wiley & Sons, Inc Types of Transmission Analog transmissions Analog data transmitted in analog form (vary continuously) Examples of analog data being sent using analog transmissions are broadcast TV and radio Digital transmissions Made of square waves with a clear beginning and ending Computer networks send digital data using digital transmissions. .
