Chapter 6 Telecommunications, Networks, and Wireless Computing 8.1 Telecommunications, Networks, and Wireless Computing SESSION 8

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.2 TELECOMMUNICATIONS Telecommunications: Communication of all types of information, including digital data, voice, fax, sound, and video from one location to another over some type of networkTelecommunications: Communication of all types of information, including digital data, voice, fax, sound, and video from one location to another over some type of network Network: A group of computers and associated peripheral devices connected by a communication channel of sharing information and other resources among usersNetwork: A group of computers and associated peripheral devices connected by a communication channel of sharing information and other resources among users

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.3 SENDER RECEIVER MEDIUM Basic Communications Model

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.4 Text Voice Image Video Types of Data

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.5 Three Major Developments Shaping Contemporary Systems 1.Client/server computing 2.Packet switching 3.TCP/IP and other communications standards The Corporate Telecommunications System Features of Contemporary Telecommunications Systems

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.6 The Corporate Telecommunications System A corporate telecommunications system Figure 8-1

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.7 Client/Server Computing Powerful personal computers connect to network with one or more server computers Has extended networking to parts of business that could not be served by centralized architecture Processing load balanced over many smaller machines The Corporate Telecommunications System Features of Contemporary Telecommunications Systems

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.8 Packet Switching Messages broken into “packets” before transmission Packets include destination and error-checking information Packets travel independently using routers; reassembled into original message at destination The Corporate Telecommunications System Features of Contemporary Telecommunications Systems

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.9 The Corporate Telecommunications System Packet-switched networks and packet communications Figure 8-2

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.10 Packet Switching Packet switching breaks transmissions into packets When a packet arrives at a switch, the switch must decide where to send the packet next Switch A B C D E Trunk Line

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.11 TCP/IP Transmission Control Protocol/Internet Protocol Open suite of protocols for connectivity developed in 1970s Provides standards for breaking messages into packets, routing them to destination addresses, and reassembling them at end Allows for communication regardless of hardware/software The Corporate Telecommunications System Features of Contemporary Telecommunications Systems

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.12 TCP/IP: Four-Layer Reference Model 1.Application layer: Communication between applications and other layers 2.Transport layer: Acknowledging and sequencing packets to/from application 3.Internet layer: Addressing, routing, packaging data packets 4.Network interface layer: Placing packets on and receiving them from network medium The Corporate Telecommunications System Features of Contemporary Telecommunications Systems

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.13 The Corporate Telecommunications System The Transmission Control Protocol/Internet Protocol (TCP/IP) reference model Figure 8-3

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.14 Communication Media/Channels  Guided Media:  Twisted Pair  Coaxial Cable  Optical Fiber  Unguided Media:  Microwave  Satellite  Broadcast Radio

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.15 Twisted Pair Coaxial Cable Optical Fiber Guided Media

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.16 Analogue signal: a continuous wave Digital: a discrete set of on (1) and off (0) electronic bursts rather than a continuous wave Analog and digital signals

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.17

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.18 Microwave- “Line of sight” media: antennas need to see each other Unguided Media: Microwave

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.19 Unguided Media: Satellite

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.20

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.21 Transmission Speed Bps: Bits per second Baud rate: Rate of signal changes One signal change = cycle Transmission capacity is function of frequency Bandwidth: Range of frequencies accommodated on a particular channel The Corporate Telecommunications System Transmission Media

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.22 The Corporate Telecommunications System Transmission Speed Transmission Media Twisted wireUp to 100 MbpsLow cost MicrowaveUp to 200+ Mbps SatelliteUp to 200+ Mbps Coaxial cableUp to 200 Mbps Fiber-optic cableUp to 6+ TbpsHigh cost

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.23  By geographic span  Local Area Network (LAN)  Wide Area Network (WAN)  By topology (physical)  Star  Bus  Ring  Mesh  By architecture (logical)  Peer to peer versus client-server  Centralized versus distributed versus hybrid Computer Networks

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.24 Network Topology: STAR

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.25 Network Topology: Bus

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.26 Network Topology: Ring

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.27 Communications Networks Network topologies Figure 8-8

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.28 Local Area Networks Encompass a limited distanceEncompass a limited distance Require its own communication channelsRequire its own communication channels Support high volumes of data and functions requiring high transmission speedSupport high volumes of data and functions requiring high transmission speed Gateway, router, Network Operating System (NOS)Gateway, router, Network Operating System (NOS) COMMUNICATIONS NETWORKS

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.29 A Local Area Network (LAN) COMMUNICATIONS NETWORKS

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.30 Wide Area Networks (WANs) Span large geographical distanceSpan large geographical distance Consist of variety of switched and dedicated lines, satellite, and microwave technologiesConsist of variety of switched and dedicated lines, satellite, and microwave technologies COMMUNICATIONS NETWORKS

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.31

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.32

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.33

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.34 Use radio waves to connect stations b: Current standard; 54 Mbps in 2.4 GHz range Infrastructure mode: Wireless devices communicate with wired LAN via access points Ad-hoc mode: Peer-to-peer mode; wireless devices communicate with each other directly Communications Networks Wireless Networks: Wi-Fi and Bluetooth

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.35 Communications Networks An wireless LAN

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.36 Hot spot: Geographic location in which an access point provides public Wi-Fi network service Bluetooth: Standard for wireless personal area networks that can transmit up to 722 Kbps within 10-meter area Communications Networks Wireless Networks: Wi-Fi and Bluetooth

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.37 Is the World Falling for Wi-Fi? Textbook Page 280 Case Analysis

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.38 Frame relay Asynchronous transfer mode (ATM) Integrated Services Digital Network (ISDN) Digital subscriber line (DSL) T1 line Network convergence VAN: Value Added Network Communications Networks Broadband Network Services and Technologies

Chapter 6 Telecommunications, Networks, and Wireless Computing Eliminates telephone tag and costly long-distance telephone charges Groupware Enables work groups at different locations to participate in discussion forums and work on shared documents and projects Electronic Business and Electronic Commerce Technologies Electronic Mail and Groupware

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.40 Voice mail Digitizes spoken message and transmits it over a network Fax Digitizes and transmits documents over telephone lines Electronic Business and Electronic Commerce Technologies Voice Mail and Fax

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.41 Teleconferencing Ability to confer with a group of people simultaneously Data conferencing Two or more users can edit and modify data files simultaneously Videoconferencing Participants are able to see each other over video screens Electronic Business and Electronic Commerce Technologies Teleconferencing, Dataconferencing, and Videoconferencing

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.42 Digital Information Services: Online services providing general and business information, such as LexisNexis, AOL, Dow Jones News Distance learning Education or training delivered over a distance to individuals in one or more locations E-learning Instruction delivered online using the Internet or private networks Electronic Business and Electronic Commerce Technologies Digital Information Services, Distance Learning, and E-Learning

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.43 Computer-to-computer exchange between two organizations of standard transaction documents, such as invoices, purchase orders Minimizes paper-handling and data input; lowers transaction costs Transmits structured data with fields, unlike e- mail Electronic Business and Electronic Commerce Technologies Electronic Data Interchange

Chapter 6 Telecommunications, Networks, and Wireless Computing 8.44 Electronic Business and Electronic Commerce Technologies Electronic data interchange (EDI) Figure 8-10

Chapter 6 Telecommunications, Networks, and Wireless Computing Distance 2.Services 3.Points of access 4.Utilization 5.Cost 6.Security 7.Connectivity Developing a Business-Driven Telecommunications Plan Implementation Issues: Seven Factors