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7. Chapter. Telecommunications, the Internet, and Wireless Technology. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology. Telecommunications and Networking in Today’s Business World.

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  1. 7 Chapter Telecommunications, the Internet, and Wireless Technology

  2. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World • Most basic computer network: Two or more interconnected computers • Major hardware, software, transmission components used in simple network: • Client computer • Dedicated server computer • Network interfaces (NICs) • Network operating system (NOS) • Hub or switch • Routers: • Device used to communicate with other networks

  3. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World Components of a Simple Computer Network Illustrated here is a very simple computer network, consisting of computers, a network operating system residing on a dedicated server computer, cable (wiring) connecting the devices, network interface cards (NIC), switches, and a router. Figure 7-1

  4. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World • Networks in large companies may include • Hundreds of local area networks (LANs) linked to firmwide corporate networks • Multiple powerful servers • Corporate Web site, corporate intranet, extranet • Back-end systems for sales, financial, purchasing transactions • Telephone network, videoconferencing • Mobile WiFi network • Key issue: Integration of disparate systems • Alleviated as networks digitize, use Internet standards

  5. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World Corporate Network Infrastructure Today’s corporate network infrastructure is a collection of many different networks from the public switched telephone network; to the Internet; to corporate local area networks linking workgroups, departments, or office floors. Figure 7-2

  6. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World • Key digital networking technologies • Client/server computing • Clients linked through network controlled by server computer • Packet switching • Method of slicing digital messages into packets, sending packets along different communication paths as they become available, and then reassembling packets once they arrive at their destinations • TCP/IP and connectivity standards • Protocol: Set of rules and procedures governing transmission of information between two points in network • TCP/IP: Suite of protocols

  7. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World Packet-Switched Networks and Packet Communications Data are grouped into small packets, which are transmitted independently over various communications channels and reassembled at their final destination. Figure 7-3

  8. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World • TCP/IP: Suite of protocols developed for U.S. Dept. of Defense • Transmission Control Protocol (TCP): Handles movement of data between computers • Internet Protocol (IP): Handles assembly, delivery, disassembly of packets • TCP/IP allows two computers of different hardware and software platforms to communicate • Four-layer TCP/IP reference model • Application layer • Transport layer • Internet layer • Network interface layer

  9. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World The TCP/IP Reference Model This figure illustrates the four layers of the TCP/IP reference model for communications. Figure 7-4

  10. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks • Signals: digital vs. analog • Analog: Represented by continuous waveform • Digital: Discrete, binary waveform • Data as strings of two states: one bit, zero bits / on-off electrical pulses • Modem needed to translate between analog and digital • Types of networks (geographic scope) • Local area network (LAN) • Campus area network (CAN) • Metropolitan area network (MAN) • Wide area network (WAN)

  11. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks Functions of the Modem A modem is a device that translates digital signals from a computer into analog form so that they can be transmitted over analog telephone lines. The modem also translates analog signals back into digital form for the receiving computer. Figure 7-5

  12. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks • Ethernet: Dominant LAN standard at physical network level • Types of networks (network architecture) • Peer-to-peer or client/server • Types of networks (topology) • Star: All network components connect to single hub • Bus: Signals travel in both directions along single transmission segment • Most common Ethernet topology • Ring: Connects network components in closed loop

  13. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks Network Topologies The three basic network topologies are the bus, star, and ring. Figure 7-6

  14. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks • Physical transmission media • Twisted wire • Pairs of twisted copper wire • Older type of transmission medium • Most common LAN cabling: Cat5 cable • Coaxial cable • Single, thickly insulated copper wire • Used for longer runs

  15. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks • Physical transmission media • Fiber optics and optical networks • Strands of clear glass fiber • Used for Internet backbone • Optical networks can boost capacity by using multiplexing (DWDM) - using different wave lengths to carry separate streams of data over same strand

  16. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks • Wireless transmission media • Microwave systems • High-frequency radio signals that follow straight line and require transmission stations or satellites to act as relay • Cellular telephones • Radio towers placed in adjacent geographic areas (cells)

  17. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks BP Amoco’s Satellite Transmission System Satellites help BP Amoco transfer seismic data between oil exploration ships and research centers in the United States. Figure 7-7

  18. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks • Transmission speed • Bits per second (bps): Used to measure total amount of data that can be transmitted • Hertz (cycles per second): Frequency of medium, affects transmission capacity • Bandwidth: Difference between highest and lowest frequencies that can be accommodated on channel

  19. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks • Broadband network services and technologies • Frame relay (56 Kbps to 40+ Mbps) • Packages data into frames for high-speed transmission over reliable circuits that require less error checking than packet switching • Asynchronous Transfer Mode (ATM) (1.5 Mbps to 9+Gbps) • Parcels data into 53-byte cells for high-speed transmission • Can transmit data, video, and audio over same network • Integrated Services Digital Network (ISDN) (128 Kbps to 1.5 Mbps) • Dial-up network access standard that can integrate voice, data, and video services

  20. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks • Broadband network services and technologies • Digital subscriber line (DSL) (1 Mbps – 9 Mbps) • Dedicated telephone network broadband Internet access • Cable Internet connections (Up to 10 Mbps) • Dedicated cable network broadband access • T lines (1.5 Mbps to 45 Mbps) • Dedicated lines for high-speed data transmission and Internet connection

  21. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • What is the Internet? • World’s most extensive public communication system, rivaling global telephone system • World’s largest implementation of: • Client/server network • Internetworking • Internet service provider: • Commercial organization with permanent connection to Internet • Sells temporary connections to retail subscribers

  22. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Internet addressing • IP address • Assigned to each computer on Internet • 32-bit number: four strings of numbers ranging from 0 to 255 separated by periods • E.g. 207.46.250.119 • Messages decomposed into packets, each carrying destination IP address

  23. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Domain Name System • Converts IP addresses to domain names • DNS servers maintain database of domain names mapped to IP addresses • Domains: E.g. sales.google.com • Root domain (“.”) • Top-level domain (.gov, .com, .edu, etc.) • Second-level domain (e.g. “google”) • Third-level domains/hosts (“computer1.sales.google.com”)

  24. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet The Domain Name System The Domain Name System is a hierarchical system with a root domain, top-level domains, second-level domains, and host computers at the third level. Figure 7-8

  25. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Internet architecture • Trunk lines: High-speed backbone networks owned by long-distance telephone companies (network service providers) or national governments • Regional networks lease access to ISPs, private companies, government institutions • Regional telephone, cable companies lease access to retail users and businesses

  26. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet Internet Network Architecture The Internet backbone connects to regional networks, which in turn provide access to Internet service providers, large firms, and government institutions. Network access points (NAPs) and metropolitan area exchanges (MAEs) are hubs where the backbone intersects regional and local networks and where backbone owners connect with one another. MAEs are also referred to as Internet Exchange Points. Figure 7-9

  27. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Internet governance • Internet policies established by several professional organizations and government bodies • IAB: Defines overall structure of Internet • ICANN: Assigns IP addresses • W3C: Sets programming standards, HTML standards for Web • These organizations influence government agencies, network owners, ISPs, and software developers • Internet must conform to local national law and technical infrastructure • Internet paid for by connection services and fees

  28. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • IPv6 • IPv4 (32 bit addresses) provides 4.5 billion addresses • Less than one address for each of Earth’s 6.5 billion • IPv6 (128 bit addresses) will provide 3.4 X 1038 addresses • Millions of addresses for each person • Internet2 and Next-Generation Internet (NGI) • Consortia of universities, businesses, government agencies addressing current shortcomings of Internet • Better performance, more bandwidth • More effective routing • Advanced applications for distributed computing, etc.

  29. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Internet services • Client/server technology • Client: • Software (e.g. Web browsers) on personal computers or information appliances • Servers: • Store data (e-mails, Web pages) • Transfer data to clients • Run services, implemented by one or more software programs, that clients can access • E.g. Telnet, FTP, World Wide Web, newsgroups, chat

  30. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet Client/Server Computing on the Internet Client computers running Web browser and other software can access an array of services on servers over the Internet. These services may all run on a single server or on multiple specialized servers. Figure 7-10

  31. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • World Wide Web: Most popular Internet service • Web pages: Formatted using Hypertext Markup Language (HTML) with embedded links that connect documents to one another and that also link pages to other objects, such as sound, video, or animation files • Hypertext Transfer Protocol (HTTP): Communications standard used to transfer pages on Web • Uniform resource locator (URL): Full address of web page, including protocol, domain name, directory path, and file name • E.g.: http://www.megacorp.com/content/features/082602.html

  32. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Web servers: Software for locating and managing stored Web pages, typically run on dedicated computers • E.g. Apache HTTP Server, Microsoft IIS • Web site: Collection of Web pages linked to home page • Webmaster: Person in charge of organization’s Web site • Search engines: Allow finding information on Web of 50 billion+ pages nearly instantly • Serve as major portals to Web • Early search engines: Simple keyword indexes of visited pages • Yahoo!: Originally organized favorite Web sites into directory lists

  33. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Search engines: • Google: Utilized new page ranking system and indexed combinations of words • Search engine marketplace very competitive • Search engines have become major shopping tools • Search engine marketing: • Search engine includes paid, sponsored links and advertisements in search results • Fastest growing form of Internet advertising • Shopping bots: • Use intelligent agent software for searching Internet for shopping information

  34. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet Major Web Search Engines Google is the most popular search engine on the Web, handling nearly 50 percent of all Web searches. Figure 7-11

  35. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet How Google Works Figure 7-12 The Google search engine is continuously crawling the Web, indexing the content of each page, calculating its popularity, and storing the pages so that it can respond quickly to user requests to see a page. The entire process takes about one-half second.

  36. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Web 2.0 • Second-generation interactive Internet-based services • Mashups: Software services that mix and match content or software components to create something entirely new • Blog: informal chronological Web site where subscribing individuals can publish stories, opinions, and links to other Web sites • RSS (Rich Site Summary or Really Simple Syndication): Syndicates Web site content so it can be pulled from Web sites and fed automatically to subscribed users • Wikis: Collaborative Web sites where visitors can add, delete, or modify content on site, including work of previous authors

  37. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Intranets: Private networks using Internet standards • Protected from public visits by firewalls • Extranets: Limited area of intranet designed for access by authorized vendors and customers • Technologies and tools for communication and e-business • E-mail • Chat, instant messaging • Electronic discussions • Groupware • Electronic conferencing

  38. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Internet telephony: • Telephone voice transmission over Internet or private networks • Voice over IP (VoIP): Uses Internet Protocol (IP) to deliver voice information using packet switching, avoiding tolls charged by local and long-distance telephone networks • Fastest-growing form of telephone service in United States • Can reduce communication and network management costs by 20 to 30 percent • Flexible technology: Phones can be added or moved to different offices without rewiring or reconfiguring network

  39. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet How IP Telephony Works An IP phone call digitizes and breaks up a voice message into data packets that may travel along different routes before being reassembled at the final destination. A processor nearest the call’s destination, called a gateway, arranges the packets in the proper order and directs them to the telephone number of the receiver or the IP address of the receiving computer. Figure 7-13

  40. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet • Virtual private networks • Secure, encrypted, private network configured within public network, like Internet • Provide network infrastructure for combining voice and data networks • Can be established with different, competing protocols • E.g. Point-to-Point Tunneling Protocol (PPTP) • Tunneling: Packets of data are encrypted and wrapped inside IP packets

  41. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Internet A Virtual Private Network Using the Internet This VPN is a private network of computers linked using a secure “tunnel” connection over the Internet. It protects data transmitted over the public Internet by encoding the data and “wrapping” them within the Internet Protocol (IP). By adding a wrapper around a network message to hide its content, organizations can create a private connection that travels through the public Internet. Figure 7-14

  42. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution • Wireless devices: Have become portable computing platforms • Cell phones • Laptops • Handhelds • Personal digital assistants (PDAs) • E-mail handhelds • Smart phones • Cellular systems: • Mobile phones enable millions to communicate and access Internet in countries where conventional phone or Internet service is expensive or unavailable. More mobile phones than PCs (3 billion vs 1 billion)

  43. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution • Cellular standards • Global system for mobile communication (GSM) • Europe, most of world, and some U.S. systems (AT&T) • Code Division Multiple Access (CDMA) • A widely used standard in U.S. (Verizon) • Cellular Generations: • 384 Kbps, good for e-mail, and OK at downloading Web pages. • 3G (third generation) networks: 384 Kbps to 2 Mbps, acceptable for broadband access • 2.5G networks: Interim solution; 30 - 144 Kbps. iPhone uses AT&T EDGE 2.G network maximum speed 236; actual about 80 Kbps

  44. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution • Mobile wireless standards for Web access • Wireless Application Protocol (WAP) • System of protocols, technologies enabling cell phones and other devices with tiny display screens, low bandwidth, and minimal memory to access Web-based information and services • Uses: • Wireless markup language (WML) based on XML • Microbrowsers • WAP gateway to translate Web content into WML for mobile devices • Google Mobile and Yahoo! Mobile pages

  45. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution • Mobile wireless standards for Web access • I-mode • Japan’s DoCoMo mobile phone network’s wireless service • Uses compact HTML to deliver content • Easier for business to convert Web sites for mobile access • Limited geographic adoption to Asia

  46. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution WAP Versus I-Mode WAP and i-mode use alternative standards for accessing information from the wireless Web. Figure 7-15

  47. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution • Wireless computer networks and Internet access • Institute of Electrical and Electronics Engineers (IEEE) Standards for wireless networks • IEEE 802.15: PANs, Bluetooth • IEEE 802.11: LANs, Wi-Fi • IEEE 802.16: MANs, WiMax

  48. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution • Bluetooth: • IEEE 802.15 • Useful for personal area networks (PANs) • Links up to eight devices within 10-meter area using low-power, radio-based communication • Transmits up to 722 Kbps in 2.4-GHz band • Used for wireless keyboards, mice, cell phones, PDAs, printers

  49. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution A Bluetooth Network (PAN) Bluetooth enables a variety of devices, including cell phones, PDAs, wireless keyboards and mice, PCs, and printers, to interact wirelessly with each other within a small 30-foot (10-meter) area. In addition to the links shown, Bluetooth can be used to network similar devices to send data from one PC to another, for example. Figure 7-16

  50. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution • Wi-Fi • IEEE 802.11 standards • 802.11a: 54 Mbps, 5 GHz, • 802.11b: 11 Mbps, 2.4 GHz • 802.11g: 54 Mbps, 2.4 GHz, compatible with 802.11b • 802.11n: emerging standard, greater than 200 Mbps • Modes: • Infrastructure mode: Wireless devices communicate with wired LAN using access points (device with radio receiver/transmitter) • Ad hoc mode: Wireless devices communicate directly to each other • Wireless communication requires client to have wireless NICs or embedded chips to receive Wi-Fi signals

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