Our Digital World Chapter 6 Communications and Network Technologies: Connecting Through Computers © Paradigm Publishing, Inc. 1 This chapter will help you be able to: • Define computer networking and its uses. • Describe a communications system and how data is exchanged. • Distinguish various types of transmission media. • Recognize the role of network standards and protocols. • Describe various networking devices and software. • Explain the importance of network security. © Paradigm Publishing, Inc. 2 Main Topics • • • • • • • • 6.1 6.2 6.3 6.4 6.5 6.6 6.7 6.8 How Does the World Use Networking? Exploring Communications Systems Transmission Systems Communications Standards and Protocols Network Classifications Networking Devices and Software Securing a Network Interesting Trends in Networking © Paradigm Publishing, Inc. 3 Why Should You Care? • Communications systems allow computing devices to send and receive data. • Networks allow sharing of files, Internet connections, and devices. © Paradigm Publishing, Inc. 4 6.1 How Does the World Use Networking? © Paradigm Publishing, Inc. 5 The Many Uses of Networks • • • • • A way to share files and resources. Communicate with others. Intranets and extranets. Home networks. The Internet. © Paradigm Publishing, Inc. 6 • computer network • intranet • extranet Terms to Know © Paradigm Publishing, Inc. 7 Ask Yourself… The Internet is a global network of a. b. c. d. microwave towers. social networks. several networks linked together. intranets. © Paradigm Publishing, Inc. 8 6.2 Exploring Communications Systems © Paradigm Publishing, Inc. 9 Communications Systems Illustrated © Paradigm Publishing, Inc. 10 Types of Signals • Analog and digital. • Voice transmitted as analog on phone lines. • Computers require a digital signal. • Newer technologies don’t require the conversion. © Paradigm Publishing, Inc. 11 Analog and Digital Signals © Paradigm Publishing, Inc. 12 Transmission Speed • • • • Data moves at different speeds. Frequency and bandwidth. Network traffic. Broadband allows the transmission of a large amount of data at fast speed. © Paradigm Publishing, Inc. 13 Frequency Speeds © Paradigm Publishing, Inc. 14 • communications system • network protocol • analog signal • digital signal • modem • frequency • bandwidth Terms to Know © Paradigm Publishing, Inc. 15 • • • • • • broadband kilobit per second (Kbps) megabit per second (Mpbs) gigabit per second (Gbps) terabit per second (Tbps) petabit per second (Pbps) Terms to Know © Paradigm Publishing, Inc. 16 Ask Yourself… The number of pieces of data that can be transmitted over a communications medium is called a. b. c. d. frequency. bandwidth. broadband. wavelength. © Paradigm Publishing, Inc. 17 6.3 Transmission Systems © Paradigm Publishing, Inc. 18 Wired Transmissions • Wired networks still in use. • Various types of cables: – Coaxial – Twisted-pair – Fiber-optic © Paradigm Publishing, Inc. 19 Wired Transmissions • Coaxial • Twisted-pair • Fiber-optic © Paradigm Publishing, Inc. 20 Wireless Transmissions • Cellular, microwave, and satellite. • Radio waves. • Signal strength and frequency. © Paradigm Publishing, Inc. 21 Cellular Technology © Paradigm Publishing, Inc. 22 Microwave Technology © Paradigm Publishing, Inc. 23 Satellite Communications © Paradigm Publishing, Inc. 24 • • • • • • • twisted-pair cable coaxial cable fiber-optic cable cellular network cellular transmission microwave satellite communication Terms to Know © Paradigm Publishing, Inc. 25 Ask Yourself… A cellular network sends transmissions using a. b. c. d. microwave towers. T-lines. fiber-optic cable. cell towers. © Paradigm Publishing, Inc. 26 6.4 Communications Standards and Protocols © Paradigm Publishing, Inc. 27 What Are Standards and Protocols? • Addressing issues of compatibility. • Standards organizations. • Communications standards called protocols. © Paradigm Publishing, Inc. 28 Networking in Space • Why do we need a data communications network in space? • How will a network in space be used in the near future? • How might a network in space be used in the distant future? © Paradigm Publishing, Inc. 29 Network Transport Standards • Ethernet. • Token ring. • TCP/IP. © Paradigm Publishing, Inc. 30 Wireless Networking Standards • • • • • Wi-Fi. WiMAX. Bluetooth. Radio Frequency Identification (RFID). Wireless Application Protocol (WAP). © Paradigm Publishing, Inc. 31 Mobile Internet Usage © Paradigm Publishing, Inc. 32 • Public networks likely to be unsecured. • Don’t access financial accounts. • Secure your home wireless network. Playing It Safe © Paradigm Publishing, Inc. 33 • standards • American National Standards Institute (ANSI) • Institute of Electrical & Electronics Engineers (IEEE) • protocol • Ethernet Terms to Know © Paradigm Publishing, Inc. 34 • • • • • • • • token ring token TCP/IP packet packet switching Wi-Fi 802.11 standard hotspot Terms to Know © Paradigm Publishing, Inc. 35 • • • • • • • WiMAX 4G standard Bluetooth Radio Frequency Identification (RFID) Wireless Application Protocol (WAP) email server webmail Terms to Know © Paradigm Publishing, Inc. 36 Ask Yourself… Computer standards allow a. b. c. d. different devices to talk to each other. data files to be decrypted. you to create email messages. manufacturers to design computing devices. © Paradigm Publishing, Inc. 37 6.5 Network Classifications © Paradigm Publishing, Inc. 38 Types of Networks • Local Area Networks (LAN). • Metropolitan Area Networks (MAN). • Wide Area Networks (WAN). © Paradigm Publishing, Inc. 39 Network Architecture • • • • Sharing network resources. Client/server. Peer-to-peer (P2P). Internet peer-to-peer (P2P). © Paradigm Publishing, Inc. 40 Client/Server Architecture © Paradigm Publishing, Inc. 41 Peer-to-Peer Architecture © Paradigm Publishing, Inc. 42 Network Topologies • Arrangement of devices in a network. • Three kinds: – Bus topology – Ring topology – Star topology © Paradigm Publishing, Inc. 43 Bus Topology © Paradigm Publishing, Inc. 44 Ring Topology © Paradigm Publishing, Inc. 45 Star Topology © Paradigm Publishing, Inc. 46 • • • • • • • • local area network (LAN) server wireless LAN (WLAN) metropolitan area network (MAN) wide area network (WAN) network architecture client/server network client Terms to Know © Paradigm Publishing, Inc. 47 • • • • • • • distributed application architecture peer-to-peer (P2P) network Internet peer-to-peer (P2P) network topology bus topology ring topology star topology Terms to Know © Paradigm Publishing, Inc. 48 Ask Yourself… Which type of network server is shown here? a. b. c. d. LAN. MAN. WLAN. WAN. © Paradigm Publishing, Inc. 49 6.6 Networking Devices and Software © Paradigm Publishing, Inc. 50 Network Devices • Network devices include: – Modems. – Network adapters. – Wireless access points and routers. – Repeaters. – Hubs and switches. – Gateways and bridges. © Paradigm Publishing, Inc. 51 Network Devices © Paradigm Publishing, Inc. 52 Wireless Network Access Point © Paradigm Publishing, Inc. 53 Networking Operating Systems • Used for managing networks. • Installed on the central server. © Paradigm Publishing, Inc. 54 • • • • • • • • node dial-up modem DSL modem cable modem wireless modem network adapter network interface card (NIC) wireless interface card Terms to Know © Paradigm Publishing, Inc. 55 • • • • • • • • • wireless access point router wireless router repeater hub switch gateway bridge network operating system (NOS) Terms to Know © Paradigm Publishing, Inc. 56 Ask Yourself… Each device connected to a network is called a(n) a. b. c. d. modem. node. interface card. access point. © Paradigm Publishing, Inc. 57 6.7 Securing a Network © Paradigm Publishing, Inc. 58 Network Security © Paradigm Publishing, Inc. 59 • Computer security is a hot career. • Growth is due to increases in cyber attacks and Internet-based applications. Computers in Your Career © Paradigm Publishing, Inc. 60 • firewall Terms to Know © Paradigm Publishing, Inc. 61 Ask Yourself… A combination of hardware and software that stops people outside a network from sending information into it is called a. b. c. d. a network administrator. network security. a firewall. a firebreak. © Paradigm Publishing, Inc. 62 6.8 Interesting Trends in Networking © Paradigm Publishing, Inc. 63 Mobility and VoIP • Building Wi-Fi and VoIP into intranets. • Saving money. © Paradigm Publishing, Inc. 64 Cloud Computing • Software used from a network server. • Cloud services are flexible. © Paradigm Publishing, Inc. 65 Ask Yourself… A new networking trend is that companies are building this cost-saving feature into their internal networks a. b. c. d. VoIP. network servers. firewalls. cell towers. © Paradigm Publishing, Inc. 66 Our Digital World © Paradigm Publishing, Inc. 67