Communication and Networks Chapter 8 PDF

Because learning changes everything. ® Communication and Networks Chapter 8 Computing Essentials O’Leary © 2021 McGraw-Hill Education. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution pe...

Because learning changes everything. ® Communication and Networks Chapter 8 Computing Essentials O’Leary © 2021 McGraw-Hill Education. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior written consent of McGraw-Hill Education.  Learning Objectives 1. Explain connectivity, the wireless revolution, and communication systems. 2. Describe physical and wireless communications channels. 3. Differentiate between connection devices and services, including dial-up, DSL, satellite, and cellular. 4. Describe data transmission factors, including bandwidth and protocols. 5. Define networks and key network terminology, including network interface cards and network operating systems. 6. Describe different types of networks, including local, home, wireless, personal, metropolitan, and wide area networks. 7. Describe network architectures, including topologies and strategies. 8. Explain the organization issues related to Internet technologies and network security. © McGraw-Hill Education 2  Introduction We live in a truly connected society. Increased connectivity potentially means increased productivity, especially in business. You will learn more about the concept of connectivity and the impact of the wireless revolution in this chapter. © McGraw-Hill Education IS2009-06/Cultura Creative (RF)/Alamy Stock Photo 3  Communication Computer communications is the process of sharing data, programs, and information between two or more computers Numerous applications depend on communication systems, including Texting E-mail Videoconferencing Electronic commerce © McGraw-Hill Education 4  Connectivity Connectivity uses computer networks to link people and resources Connects your personal computer to other computers and resources on a network and the Internet The Wireless Revolution Single most dramatic change in connectivity in the past decade The Revolution Allows individuals to connect to the is just beginning Internet and share information from almost anywhere in the world © McGraw-Hill Education fotoinfot/Shutterstock 5  Communication Systems Communication systems are electronic systems that transmit data from one location to another. wired or wireless, every communication system has four basic elements © McGraw-Hill Education Figure 8-2 6  Basic Elements of Communication Sending and receiving devices Computer or a specialized communication device Connection devices Interface between sending and receiving device Data transmission specifications Rules and procedures that coordinate the devices Communication channel Carries the message © McGraw-Hill Education 7  Communication Channels Physical Connections using wire or cable Wireless Connections © McGraw-Hill Education 8  Wireless Connections Wireless connections do not use a solid substance to connect; uses the air itself. Most use radio waves to communicate Primary technologies used for wireless connections are cellular, Bluetooth, Wi-Fi, microwave, WiMax, and satellite connections Wi-Fi Alliance version IEEE name Ratification date Frequency utilized Maximum data rate None 802.11 1997 2.4 GHz 2 Mbps Wi-Fi 1 802.11b 1999 2.4 GHz 11 Mbps Wi-Fi 2 802.11a 1999 5 GHz 54 Mbps Wi-Fi 3 802.11g 2003 2.4 GHz 54 Mbps Wi-Fi 4 802.11n 2009 2.4 GHz & 5 GHz 600 Mbps Wi-Fi 5 802.11ac 2014 5 GHz 7.2 Gbps Wi-Fi 6 802.11ax 2019 2.4 GHz & 5 GHz 9.6 Gbps Wi-Fi 6E 802.11ax 2020 1-6 GHz 9.6 Gbps Wi-Fi 7 802.11be 2024 2.4GHz, 5GHz, 6GHz 46 Gbps © McGraw-Hill Education 9  Physical Connections Physical connection uses solid medium to connect between sending and receiving device include Twisted pair cable: two pairs of copper wire twisted together Telephone lines (2 pairs) Ethernet cables (4 pairs) Coaxial cable: single solid copper core Cable TV, high-frequency transmission cable 80 times transmission capacity more than twisted pair Fiber-optic cable: tiny glass tubes Lighter, Faster and more reliable than coax Speeds as high as 1 petabit per second © McGraw-Hill Education Kamolrat/Shutterstock; Flegere/Shutterstock; Hugh Threlfall/Alamy Stock Photo 10  Primary Wireless Technology Bluetooth (short-range) Cellular Radio communication standard Use multiple antennae to communication Wi-Fi (wireless fidelity) Satellite Uses high frequency radio Uses satellites as microwave Microwave relay stations Uses high frequency radio Infrared wave signals Use infrared light wants to WiMax (extends Wi-Fi) communication over short New standard that uses distances microwave to extend WiFi GPS range Determine geographic location of the devices © McGraw-Hill Education 11  Connection Device Signals Types of signals Analog (telephone) Digital (computer) Transfer rates Mbps – million bits per second Gbps – billion bits per second Tbps – trillion bits per second © McGraw-Hill Education Figure 8-9 12  Connection Devices Modem – modulator-demodulator Modulation is the process of converting from digital to analog Demodulation is the process of converting from analog to digital Transfer rate Speed in which modems transfer data Usually measured in megabits per second (Mbps) © McGraw-Hill Education 13  Types of Modems Digital subscriber line (DSL) High speed telephone lines Cable Uses coaxial cable Wireless Also known as WWAN © McGraw-Hill Education (left): AlexLMX/Getty Images; (middle): iko/Shutterstock; (right): Alex Melnick/Shutterstock 14  Connection Services Leased lines T1 combined to form T3 and DS3 Have been replaced by OC lines Faster optical carrier lines Higher capacity Not affordable for individuals © McGraw-Hill Education 15  Connection Services - Individual Digital subscriber line (DSL) Fiber Optic Service (FiOS) Uses phone lines New technology Google and Verizon ADSL is most widely used type of DSL Satellite connection services Cable Use almost anywhere Uses existing TV cable Cellular Services Faster than DSL 4G and 5G cellular network connectivity © McGraw-Hill Education 16  Making IT Work for You ~ The Mobile Office Can telecommute from anywhere Become a one-man workforce Mobie Personal Hotspot Public Wi-Fi Hotspot Device Cloud Video Storage Conferencing © McGraw-Hill Education 17  Factors that Affect Data Transmission Bandwidth is how much information can move across the communication channel in a given amount of time Measurement of the width or capacity of the communication channel Categories of bandwidth Voiceband (or low bandwidth) – standard telephone Medium band – leased lines for high-speed Mid-range computer and mainframes Broadband for DSL, cable, satellite connections to the Internet Baseband for individual connections for computers in close range © McGraw-Hill Education 18  Protocols Communication rules for exchanging data between computers HTTPS – Hypertext Transfer Protocol Secure Widely used to protect the transfer of sensitive data TCP/IP (Transmission control protocol/Internet protocol) Most widely used protocol Each computer is identified with unique IP (Internet Protocol) address DNS – Domain name service resolves IP addresses to names Packetization – information broken down into small parts (packets) and then reassembled © McGraw-Hill Education Gravvi/Shutterstock 19  Networks A communication system that connects two or more computers so they can exchange information and share resources © McGraw-Hill Education Gravvi/Shutterstock 20  Network Terminology Nodes Router Any device connected to a network Node that forwards or routes data packets Client Switch A node that requests and uses resources from other nodes Central node that coordinates the flow of data Server Network Interface Cards (NIC) A node that shares resources with other nodes Expansion card that connects a computer to a network Directory Server Network Operating System Specialized server that managers resources Control activities of all computers on the network Host Network Administrator Computer system that can be accessed over a network Computer specialists responsible for network operations © McGraw-Hill Education 21  Network Types © McGraw-Hill Education 22  Network Architecture How the network is arranged and resources are shared Network Topology Physical arrangement of the network Network Strategy How the information and resources are shared © McGraw-Hill Education 23  Ring Network © McGraw-Hill Education Gravvi/Shutterstock 24  Star Network © McGraw-Hill Education Gravvi/Shutterstock 25  Tree Network © McGraw-Hill Education Gravvi/Shutterstock 26  Mesh Network © McGraw-Hill Education Gravvi/Shutterstock 27  Network Strategies Client/Server Network Central computers coordinate and supply services to other nodes on the network Server provides access Client nodes request the services. Server OS ex: Windows Server, macOS X Server, Linux, and Solaris Peer-to-Peer (P2P) Network All nodes have equal authority Can act as both client and server © McGraw-Hill Education 28  Organizational Networks Internet technologies support effective communication within and between organizations Intranet Private network within an organization Works like the Internet Extranet Private network that connects more than one organization Works like the Internet, but provides suppliers and other trusted partners with limited access to the organization’s networks © McGraw-Hill Education 29  Network Security Commonly used technologies to ensure network security Firewall Hardware and software that controls access to network Proxy server provides pass-through access Protects against external threats Intrusion detection system (IDS) Works with firewall to protect organization's network Analyzes all incoming and outgoing network traffic Virtual private network (VPN) Creates a secure private network connection between your computer and the organization © McGraw-Hill Education 30  Network Security Graphic © McGraw-Hill Education Gravvi/Shutterstock 31  Careers in IT Network Administrator Manages a company’s LAN and WAN networks Responsible for design, implementation, and maintenance of networks. Maintains networking hardware and software, diagnosing and repairing problems that arise Candidates usually have a bachelor’s or associate’s degree in computer science, computer technology or information systems Experience with network security and maintenance is preferred Certification and good communication skills preferred Annual salary is typically between $43 K and $84 K Upper management positions in growth © McGraw-Hill Education 32  A Look to the Future Telepresence Seeks to create the illusion that you are actually at a remote location Early implementations mainly focus on an extension of video- conferencing Telepresence will allow you to touch things in this other location—to interact with the world there through robotics and even feel this other location. © McGraw-Hill Education Egor Kotenko/123RF 33  Open Ended Questions 1. Define communications including connectivity, the wireless revolution, and communication systems. 2. Discuss communication channels, including physical connections and wireless connections. 3. Discuss connection devices including modems (DSL, cable, and wireless modems) and connection services (DSL, ADSL, cable, satellite, and cellular connection services). 4. Discuss data transmission including bandwidths (voiceband, medium band, broadband, and baseband) as well as protocols (IP addresses, domain name servers, and packetization). 5. Discuss networks by identifying and defining specialized terms that describe computer networks. 6. Discuss network types including local area, home, wireless, personal, metropolitan, and wide area networks. 7. Define network architecture including topologies (bus, ring, star, tree, and mesh) and strategies (client/server and peer-to-peer). 8. Discuss organization networks including Internet technologies (intranets and extranets) and network security (firewalls, proxy servers, intrusion detection systems, and virtual private networks). © McGraw-Hill Education 34  End of Main Content Because learning changes everything. ® www.mheducation.com © 2021 McGraw-Hill Education. All rights reserved. Authorized only for instructor use in the classroom. No reproduction or further distribution permitted without the prior written consent of McGraw-Hill Education.