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Chapter 5: Telecommunications, Wireless Technologies, and Computer Networks. Succeeding with Technology: Second Edition. Objectives. Understand the fundamentals of data communications and the criteria for choosing a communications medium
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Chapter 5: Telecommunications, Wireless Technologies, and Computer Networks Succeeding with Technology: Second Edition
Objectives • Understand the fundamentals of data communications and the criteria for choosing a communications medium • Explain how networking media, devices, and software work together to provide data networking services, and describe the benefits of various types of media Succeeding with Technology
Objectives (continued) • List and describe the most popular forms of wireless telecommunications technologies • List the different classifications of computer networks and their defining characteristics, and understand the basics of wireless home networking Succeeding with Technology
Fundamentals of Telecommunications • Communications • Transmission of a signal by way of a medium • Signal • Contains message comprised of data and information • Communication medium • Anything that carries a signal between a sender and a receiver Succeeding with Technology
Telecommunications and Data Communications • Telecommunications • Electronic transmission of signals for communications • Data communications • Electronic transmission and reception of digital data • Telecommunications network • Connects communications and computing devices • Networking media • Anything that carries an electronic signal Succeeding with Technology
Characteristics of Telecommunications • Analog signal • Fluctuates continuously • Digital signal • Discrete voltage • State is either high or low • Bandwidth • Data transmission rate • Measured in bits per second (bps) • Broadband • Connection that is always on or active Succeeding with Technology
Networking Media, Devices, and Software – Networking Media • Twisted pair cable • Consists of pairs of twisted wires covered with an insulating layer • Coaxial cable • Consists of an inner conductor wire surrounded by insulation, a conductive shield, and a cover • Fiber-optic cable • Consists of thousands of extremely thin strands of glass or plastic bound together in a sheathing Succeeding with Technology
Networking Devices • Modems • Modulates and demodulates signals • Cable modem • Provides Internet access over a cable television network • DSL modem • Provides high-speed Internet service over telephone lines • Network adapter • Computer circuit board, PC Card, or USB device Succeeding with Technology
Network Control Devices • Hubs • Used as a central point for connecting a series of computers • Switches • Fundamental part of most networks • Repeaters • Connect multiple network segments • Bridges • Connect two or more network segments Succeeding with Technology
Network Control Devices (continued) • Gateways • Network points that act as an entrance to another network • Routers • Can divide a single network into two logically separate networks • Wireless access point • Receives and transmits data to wireless adapters • Firewall • Device or software that filters the information coming onto a network Succeeding with Technology
Industrial Telecommunications Media and Devices • Microwave transmission • Also called terrestrial microwave • Line-of-sight medium • Communications satellite • Basically a microwave station placed in outer space Succeeding with Technology
Industrial Hardware • T1 line • Carries twenty-four 64-Kbps signals on one line • T3 line • Carries 672 signals on one line • Devices commonly used to control and protect industrial-level telecommunications: • Multiplexer • Communications processor • Encryption devices Succeeding with Technology
Networking Software • Monitors the load, or amount of traffic, on the network • Can provide data security and privacy • Network administrator • Person responsible for setting up and maintaining the network Succeeding with Technology
Networking Software (continued) • Network Operating Systems • Perform same functions for network as operating system software performs for a computer • Network Management Software • Facilitates monitoring of individual computers and shared hardware • Communications Protocols and Standards • Ethernet: most widely used network standard for private networks Succeeding with Technology
Wireless Telecommunications Technology - Cell Phone Technologies • Cellular network • A radio network • Geographic area is divided into cells with a transceiver antenna and station at the center of each cell • Cellular carrier • Company that builds and maintains cellular network • Provides cell phone service to the public Succeeding with Technology
Cellular Service Plans • Calling plans are defined by usage in three time frames: • Whenever, or anytime, minutes with no time restrictions • Weeknight minutes • Monday through Friday, 9:00 p.m. to 5:59 a.m. or 6:59 a.m. • Weekend minutes • Saturday 12:00 a.m. to Sunday 11:59 p.m. Succeeding with Technology
Pagers • Small, lightweight devices that receive signals from transmitters • Types of paging systems • National and regional systems • Set up transmission towers to cover large geographic areas • On-site paging systems • Use small desktop transmitters to send pages over a small wireless network Succeeding with Technology
Global Positioning Systems • Uses satellites to pinpoint the location of objects on earth • Using a GPS receiver and a network of 24 satellites • GPS can tell exact location of receiver on the earth’s surface • GPS • Originally developed for national security and later extended for public use Succeeding with Technology
Wireless Fidelity and WiMAX • Wireless fidelity (Wi-Fi) • Makes use of access points to wirelessly connect users to networks within a range of 250–1000 • Standards • Known as the 802.11 family of standards • Developed by the Institute of Electrical and Electronics Engineers (IEEE) • Developed to support wireless computer networking within a limited range at broadband speeds Succeeding with Technology
Wireless Fidelity and WiMAX (continued) • WiMAX • Known as IEEE 802.16 • Faster and longer range than Wi-Fi • WiMAX antenna has 31-mile range • Perfect for city-wide Internet access • Seattle’s Space Needle has a WiMAX antenna • Intel and Nokia are strongly supporting WiMAX Succeeding with Technology
Bluetooth • Enables digital devices to communicate directly with each other wirelessly over short distances • Communicates at speeds of up to 1 Mbps within a range of up to 33 feet (10 meters) • Can connect devices to a computer network using access points like Wi-Fi • Bluetooth and Wi-Fi • Compete in some areas, but have unique qualities Succeeding with Technology
Infrared Transmission • Involves sending signals through the air via light waves • Slower than both Bluetooth and Wi-Fi • Uses light rather than broadcast technology • Ideal for secure data transmissions Succeeding with Technology
Radio Frequency Identification (RFID) • Uses tiny transponders in tags that can be • Attached to merchandise or other objects • Read using an RFID transceiver or reader for the purpose of identification • Primarily used to track merchandise from supplier to retailer to customer Succeeding with Technology
Networks and Distributed Computing • Within a private network • Computing resources are shared in order to maximize computing power • Computer • Includes devices for input, processing, storage, and output • Components can be distributed throughout a computer network Succeeding with Technology
Computer Networking Concepts • Nodes • Devices attached to a network • Workstations • Computers attached to a network • Localresources • Files, drives, or other peripheral devices connected to the workstation and accessible via the network • Networkresources • Workstation accesses over the network • Distributed Computing • Multiple remote computers working together Succeeding with Technology
Network Types • Personal area network (PAN) • Interconnecting personal information technology devices • Local Area Network (LAN) • Connects computer systems within same building • Intranet • Uses protocols of the Internet and the Web within the confines of a private network • Virtual Private Network (VPN) • Enables private Internet communications Succeeding with Technology
Network Types (continued) • Metropolitan area network (MAN) • Connects networks within a city or metropolitan-size area into a larger high-speed network • Wide area network (WAN) • Connects LANs and MANs between cities, across country, and around the world • Global Networks • A WAN that crosses an international border • Electronic Data Interchange (EDI) • Connects corporate computer systems Succeeding with Technology
Home Networks • Allow residents to • Share a single Internet connection • Share a single printer between computers • Share files such as images, music, and programs • Back up copies of important files to another PC for safekeeping • Participate in multiplayer games. • Share output from devices such as a DVD player or Webcam Succeeding with Technology
Summary • Telecommunications • Refers to the electronic transmission of signals for communication • Types of cables used in telecommunications • Twisted pair cables, coaxial cable, and fiber optic cable • Networking devices include • Modems, network adapters, network control devices, RFID devices, and pagers Succeeding with Technology
Summary (continued) • Cellular network • Radio network • Geographic area is divided into cells with a transceiver antenna (tower) and station at the center of each cell • Server computers • Used to distribute data, files, and programs to users, or clients, on the network • Home networks • Used to share hardware, files, and a common Internet connection Succeeding with Technology