Essentials of Management Information Systems.11E.Laudon.CH07

Editor's Notes

• #2: This chapter discusses the principle technologies used in networking and the Internet. Ask students what the difference is between a network and the Internet. Why is networking so important to modern organizations?
• #3: How many students have wireless networks at home? How many have a smartphone that uses a 3G or 4G network? What’s the difference between a 4G network and Wi-Fi? How many students have seen an RFID tag?
• #5: New slide
• #8: This slide discusses recent developments in networking technologies. Ask students to give an example of convergence. How fast is broadband today? How many of your students have broadband? Note that in 2000, typical Internet access speeds were 56 kbps over a telephone line, costing 25 cents per kilobit, whereas today broadband speeds are 1 to 5 mbps, costing 1 cent per kilobit (or 10 cents per gigabit). Are students aware of how fast their Internet connections are at home, school, or work? Ask students if they know the speed of their cell phone’s Internet connection. The point here is to try and raise awareness of telecommunications systems among students.
• #9: This slide describes what a network is along with the components that you will find in a simple network (illustrated on the next slide.) Ask students to describe the function of an NIC. What is a connection medium? Ask students to describe the purpose of a hub, switch, and router.
• #10: This graphic illustrates the components of a simple network. Although the NOS is shown as part of the server, note that, depending on the type of software, an NOS may also be designed to reside on client computers (these are called peer-to-peer networks). Do some students have a home computer network? Ask them to describe the elements of the network.
• #11: This slide looks at the additional components one might expect to find in the network of a large company that has many locations and thousands of employees (illustrated on the next slide). Ask students what is meant by “backend systems.” Note that many firms are dispensing with traditional landline telephone networks and using Internet telephones that run on existing internal data networks and the Internet.
• #12: This graphic illustrates the components of a large company’s network. Note the difference between the wireless LAN, which allows wireless access within the office, and the mobile Wi-Fi network, which allows Internet access to employees outside of offices. The advantage of telephone-based wireless systems is that they do not require a Wi-Fi hotspot to work, and in fact can connect users to the entire globe through their telephone networks. Cable networks—major competitors of telephone company Internet providers—have recently developed a mobile option. Optimum Cable (Comcast) has installed neighborhood Wi-Fi hot spots, allowing cable subscribers wireless access to the Internet.
• #13: This slide and following two slides look at the main technologies in use today for networks: client/server computing, packet switching, and TCP/IP. Ask students what advantages client/server computing has over centralized mainframe computing.
• #14: This slide continues the discussion of the three main networking technologies today, looking at the second, packet switching. Note that circuit-switched networks were expensive and wasted available communications capacity—the circuit had to be maintained whether data was being sent or not. It is also important to note that packet switching enables packets to follow many different paths. What is the advantage of this capability? If one path is blocked due to an accident or power failure, the data will automatically be shifted by routers to open paths. However, in truly massive outages like the September 11, 2001 attack on the World Trade Center, nearby metropolitan servers were knocked out, and for a period of several days, Internet access was limited in the New York Metropolitan area. The notion that packet switching networks would survive a nuclear attack is highly unlikely.
• #15: This graphic illustrates how packet switching works, showing a message being split into three packets, sent along different routes, and then reassembled at the destination. Note that each packet contains a packet number, message number, and destination.
• #16: This slide continues the discussion of the three main networking technologies in use today, and looks at the third TCP/IP. Note that in a network, there are typically many different types of hardware and software components that need to work together to transmit and receive information. Different components in a network communicate with one another only by adhering to a common set of rules called protocols. In the past, many diverse proprietary and incompatible protocols often forced business firms to purchase computing and communications equipment from a single vendor. But today, corporate networks are increasingly using a single, common, worldwide standard called Transmission Control Protocol/ Internet Protocol (TCP/IP). TCP/IP actually is a suite of protocols, the main ones of which are TCP and IP. Ask students what these two main protocols are responsible for.
• #17: This graphic illustrates the four layers of the DOD reference model for TCP/IP. Note that what happens, when computer A sends a message to computer B, is that the data that computer A creates is transferred within that computer from the application layer to subsequent layers in sequence. In this process it is split into packets, and information is added at each stage, ultimately translating the packets into a form that can be transferred over the network interface. After traveling over the network interface, the packets are reassembled at the recipient computer, from the network interface layer up, ultimately for use by the application layer.
• #18: This slide looks at the types of networks that organizations use. Ask students what the differences are between digital and analog signals. Ask students to describe and distinguish between LANs, CANs, WANs, and MANs, and also to talk about their different range of operation. Note that a network can be defined by the way the clients interact (client/server versus peer-to-peer); the type of physical medium to carry signals (Ethernet, Giga Ethernet, etc.).
• #19: This graphic illustrates the differences between digital and analog signals, and shows how digital signals can be sent to other computers over analog cables such as telephone and cable lines which are analog. Note that digital signals are representations of the two binary digits, 0 and 1, and are represented logically as on and off electrical pulses (in reality as different voltages). Ask students what MODEM stands for.
• #20: This slide looks at the media involved in network transmission. Note that many of the telephone systems in buildings had twisted wires installed for analog communication, but they can be used for digital communication as well. Note that the transmission capacity of a medium (bps) is dependent on its frequency, which is measured in hertz, or cycles per second. Ask students to define bandwidth (it is the difference between the highest and lowest frequencies that can be accommodated on a single channel.)
• #21: This slide examines what the Internet is—ask students to describe it and what they use it for. The text refers to the Internet as the most extensive public communication system and the world’s largest implementation of client/server computing. Ask students how they connect to the Internet. Do any of their families use dial-up (telephone/modem)? Do any use satellite? Note that T lines are leased, dedicated lines suitable for businesses or government agencies requiring high-speed guaranteed service levels. Do students know that the Internet does not guarantee any service level, and only agrees to make a “best effort.” Ask students what an IP address is used for. Ask students why we have a domain name system, and why we don’t just use IP addresses. Note that the domain name system makes it possible for people to remember addresses.
• #22: Ask students what an IP address is used for. Ask students why we have a domain name system, and why we don’t just use IP addresses. Note that the domain name system makes it possible for people to remember addresses.
• #23: This graphic describes how the domain name system works. Note that the “root” domain is the period that is used before the top-level domain, such as .edu or .com. Give students an example Internet address, such as myserver.myspace.com and ask them what the top-, second-, and third-level domains are.
• #25: This graphic illustrates the architecture of the Internet. Note that MAEs (metropolitan area exchanges) are hubs where the backbone intersects regional and local networks and where backbone networks connect with one another.
• #26: Refer to the video cases for this chapter for more on network neutrality. Ask students if this debate is a political debate among large Internet players, or is it a moral and ethical issue? Or is this debate all about financial advantage? Principles or profits? Ask students to find analogies, such as toll highways versus freeways, or peak time pricing for electricity. Should trucks be charged a higher fee for the use of highways than autos because they cause greater wear and tear on roads given their weight? In many states, if not all, trucks pay much larger fees due to their destructive effect on highways.
• #28: This slide continues the discussion about what the Internet is, here looking at the services, or applications, that the Internet supports. Notice that the Internet comprises many more services than just e-mail and the Web. Ask students which of these services, beyond e-mail and the World Wide Web, they have used, and if they have, to describe how it works. Students who have cable Internet telephones are using VoIP. Other popular technologies that use the Internet as a platform are VoIP, unified communications, and virtual private networks. Ask students what they think is the value to business is of each of these technologies.
• #29: This graphic looks at the services that an Internet server computer can offer: Web sites (HTTP), e-mail (SMTP), file transfer (FTP), newsgroups (NNTP). It illustrates where on the path between client and backend systems these services lie.
• #30: This graphic shows how VoIP works. The voice messages are digitized and transported over the Internet in the same packet-switching method as traditional Internet data. Gateways are simply computers (network devices) that maintain the interface with the Internet in a firm.
• #31: This graphic illustrates how a virtual private network works. The rectangles A, B, C, and D represent different computers on the VPN. In a process called tunneling, packets of data are encrypted and wrapped inside IP packets. By adding this wrapper around a network message to hide its content, business firms create a private connection that travels through the public Internet.
• #32: Ask students how they would feel about e-mail and Internet monitoring as a manager—then ask how they would feel about it as an employee. Can they appreciate the ethical dilemma as well as the business upside of monitoring? As managers, would they support the idea of monitoring employee use of the Internet to ensure employees are really working and not fooling around on eBay? There’s an old saying which says “People want to be honest, especially when they are watched.” Can employees argue that their behavior while on the job is “private.” Do employees have an expectation of privacy while on the job?
• #33: This slide looks at one of the most popular services on the Internet, the Web, and the main protocols enabling the Web. The Web is an interlinked connection of Web sites, which are collections of Web pages linked to a home page. These pages are created using a text markup language call HTML, and transmitted to user’s Web browsers by HTTP. Web page addresses (URLs) are composed of the domain name of the Web site and the file location of the individual Web page. Ask students if any have created Web pages using HTML, and if so, to describe what this is like. How have they made the Web pages visible to others on the Web? There is a learning track available online that shows students how to create Web pages using basic HTML.
• #34: This slide looks at how people find information of interest on the Web. The primary method is through search engines, which today act as major portals to the Web. Ask students where their initial points of entry are on the Web, and how they find information they are interested in. Most will be Google users, but ask if they have looked at Bing, the Microsoft search engine that is showing some promise. The text discusses how big the Web is, in terms of pages. Google visited and indexed the content of more than an estimated 50 billion Web pages in 2011, but this does not include the “deep Web.” Other estimates point to “one trillion” Web pages, but many of these are duplicates. Ask students what the “deep Web” is. Web pages available only to subscribers for a fee (“premium content”) do not allow crawlers to index the pages. Shopping bots are always fun to visit in class. Ask students what they might be interested in having you shop for, and then use one of the shop bots such as Shopzilla or Pricegrabber.
• #35: This slide looks at how people find information of interest on the Web. The primary method is through search engines, which today act as major portals to the Web. Ask students where their initial points of entry are on the Web, and how they find information they are interested in. Most will be Google users, but ask if they have looked at Bing, the Microsoft search engine that is showing some promise. The text discusses how big the Web is, in terms of pages. Google visited and indexed the content of more than an estimated 50 billion Web pages in 2011, but this does not include the “deep Web.” Other estimates point to “one trillion” Web pages, but many of these are duplicates. Ask students what the “deep Web” is. Web pages available only to subscribers for a fee (“premium content”) do not allow crawlers to index the pages. Shopping bots are always fun to visit in class. Ask students what they might be interested in having you shop for, and then use one of the shop bots such as Shopzilla or Pricegrabber.
• #36: This graphic ranks the major search engines according to popularity, or percentage of total number of searches performed. Google is a clear favorite. Is this due to the superiority of their search engine results or does it involve other factors such as their clean interface, or their reach, which makes their ad platform more valuable to advertisers. Poll your class about the search engines they use.
• #37: This graphic illustrates in a very high level diagram how Google works. At the foundation of Google’s search engine are two concepts—page ranking and the indexing of combinations of words. Ask students if they have a favorite search engine, and if so, why that search is their favorite. The reality of how Google actually works is the subject of many volumes, and is beyond the scope of this book.
• #38: This slide discusses Web 2.0 services. Software mashups and widgets were discussed in Chapter 5. Ask if students use a blog reader, such as Google Reader, to read their blogs. If they have, they have used RSS to pull in the content from their blogs to read them in one place. Note that wikis are used in business to share information. The text cites the example of Motorola, whose sales reps use wikis to share sales information. Instead of developing a different pitch for each client, reps reuse the information posted on the wiki. How do companies use blogs and RSS?
• #39: New slide
• #41: This slide discusses the current standards in wireless networking. Ask students if they have any Bluetooth or wireless devices they use for computing, such as keyboards, earphones, or other. Note that in most Wi-Fi communications, wireless devices communicate with a wired LAN using an access point.
• #42: This graphic illustrates the uses of Bluetooth for a PAN. Bluetooth connects wireless keyboards and mice to PCs or cell phones to earpieces without wires. Bluetooth has low-power requirements, making it appropriate for battery-powered handheld computers, and cell phones. Most cell phones today are Bluetooth enabled, allowing them to connect to other wireless devices (like earphones) and PCs.
• #43: This graphic illustrates an 802.11 wireless LAN operating in infrastructure mode that connects a small number of mobile devices to a larger wired LAN. Most wireless devices are client machines. The servers that the mobile client stations need to use are on the wired LAN. The access point controls the wireless stations and acts as a bridge between the main wired LAN and the wireless LAN. (A bridge connects two LANs based on different technologies like your wireless network to your Blu-Ray player so you can download Internet movies from Netflix and watch them on your TV). The access point also controls the wireless stations.
• #44: This slide continues the discussion about wireless networking and Wi-Fi. Ask students if they have ever connected to the Internet through a hotspot at an airport, coffee shop, hotel, or other location. Was there any security? Ask students what other drawbacks, beside security, there are to Wi-Fi (roaming difficulties, interference). Note that wireless networks based on the upcoming 802.11n specification will solve interference problems by using multiple wireless antennas in tandem to transmit and receive data and technology to coordinate multiple simultaneous radio signals. What is this technology called? (MIMO).
• #45: This slide introduces one of two wireless technologies having a major impact on business, radio frequency ID. Ask students for examples of where RFID is used today. The text provides the example of Wal-Mart using RFID to manage inventory and supply chains. Ask students how this works.
• #46: This graphic illustrates how RFID works. Ask students if RFID potentially poses any ethical problems.
• #47: This slide introduces a second wireless technology having a major impact on business, wireless sensor networks. Note that the wireless sensors are linked into an interconnected network that routes the data to a computer for analysis.
• #48: This graphic illustrates the lower level nodes and higher level nodes at work in a wireless sensor network. Note that the server that data from the sensors is sent to acts as a gateway to a network based on Internet technology.