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 2 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 3 Fundamentals of Telecommunications Communications Signal Transmission of a signal by way of a medium Contains message comprised of data and information Communication medium Anything that carries a signal between a sender and a receiver Succeeding with Technology 4 Succeeding with Technology 5 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 6 Succeeding with Technology 7 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 8 Succeeding with Technology 9 Succeeding with Technology 10 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 11 Succeeding with Technology 12 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 13 Succeeding with Technology 14 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 15 Succeeding with Technology 16 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 17 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 18 Succeeding with Technology 19 Succeeding with Technology 20 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 21 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 22 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 23 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 24 Succeeding with Technology 25 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 26 Succeeding with Technology 27 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 28 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 29 Succeeding with Technology 30 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 31 Succeeding with Technology 32 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 33 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 34 Succeeding with Technology 35 Succeeding with Technology 36 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 37 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 38 Succeeding with Technology 39 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 40 Succeeding with Technology 41 Computer Networking Concepts Nodes Devices attached to a network Workstations Computers attached to a network Local resources Files, drives, or other peripheral devices connected to the workstation and accessible via the network Network resources Workstation accesses over the network Distributed Computing Multiple remote computers working together Succeeding with Technology 42 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 43 Succeeding with Technology 44 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 45 Succeeding with Technology 46 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 47 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 48 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 49