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Editor's Notes

• #2: This slide discusses recent developments in networking technologies. Ask students to give other examples of convergence. How fast is broadband today? Do all of the students have broadband? Note that in 2000, typical Internet access speeds were 56 kbps over a telephone line, costing 25 cents per kilobit, while today broadband speeds are 1-15 mbps, costing less than 1 cent per kilobit. 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 student awareness of telecommunications systems, and their capacities.
• #3: 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 a NIC. What is a connection “medium”? Ask students to describe the purpose of a hub, switch, and router.
• #4: This graphic illustrates the components of a simple network. While 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. Do some students have a home computer network? Ask them to describe the elements of the network.
• #5: 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.
• #6: 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 – do not really have a mobile option although Optimum Cable (Comcast) and several other firms are developing a Wi-Max capability that could potentially serve an entire metropolitan area. This development will take many years, and in 2010 many Wi-Max metropolitan experiments were behind schedule. Towerstream is one of the largest Wi-Max providers in the U.S. and in 2011 announced it was developing coverage for Middleton, Rhode Island, and starting an installation in Manhattan (New York City). You might ask a group of students to do research on Wi-Max in U.S. cities and report back to the class. Towerstream.com is a good place to start.
• #7: 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.
• #8: 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?
• #9: 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.
• #10: 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 each other 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.
• #11: This slide looks at the types of networks that organizations use. Ask students what the differences are between digital and analog signals. Another example of the difference between analog and digital signals is the difference between vinyl records and digital CDs and MP3s. 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 vs. peer-to-peer); the type of physical medium to carry signals (Ethernet, Fast Ethernet, etc.), and the way in which computers are connected and send signals to each other (topology).
• #12: 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.
• #13: This graphic illustrates the three main topologies in use in LANs. In a star topology, all devices on the network connect to a single hub and all network traffic flows through the hub. In an extended star network, multiple layers or hubs are organized into a hierarchy. In a bus topology, one station transmits signals, which travel in both directions along a single transmission segment. All of the signals are broadcast in both directions to the entire network. All machines on the network receive the same signals, and software installed on the client’s enables each client to listen for messages addressed specifically to it. A ring topology connects network components in a closed loop. Messages pass from computer to computer in only one direction around the loop, and only one station at a time may transmit. The ring topology is primarily found in older LANs using Token Ring networking software. Ask students which of the topologies is the most common.
• #14: 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. Also, today, telecommunications companies are starting to bring fiber optic cable into the home for high-speed Internet access. Ask students what characteristic of microwave transmission means that transmission stations must be 37 miles apart. 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.)
• #15: 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.”
• #16: 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 WWW have they 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 and virtual private networks. Ask students what the value to business is of each of these technologies. One benefit of VOIP is the ability to use unified communications.
• #17: 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 WWW have they 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 and virtual private networks. Ask students what the value to business is of each of these technologies. One benefit of VOIP is the ability to use unified communications.
• #18: 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 back-end systems these services lie.
• #19: 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.
• #20: 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 they 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 over 100 billion web pages in 2010, but this doesn’t include the “deep Web” Ask students what the “deep Web” is. Web pages a 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 like Shopzilla or Pricegrabber.
• #21: This graphic ranks the major search engines according to popularity, or percentage of total number of searches performed. Google is a clear favorite. Bing is Google’s only rival that has actually increased its market share, now about 10% and slowly growing. Is this due to the superiority of the Google search engine or does it involve other factors? Search engines may be a good example of a “winner take all” marketplace where one firm gains an advantage, and then quickly dominates the entire market. On the other hand, these concentrations of market power don’t last forever. Facebook in the space of a few years has nearly as many users as Google and potentially could rival Google in search and advertising related to search or other personal information.
• #22: This slide discusses Web 2.0 services. Ask students to give an example of a Web 2.0 application and identify what features of that application correspond to the four Web 2.0 features listed here. An example might be Facebook. Note that the Web is not just a collection of destination sites, but a source of data and services that can be combined to create applications users need. 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?
• #23: This slide discusses the next wave of improving the Web, a collaborative effort to make searching the Web more productive and meaningful for people. The text estimates that 50% of search engine queries produce meaningful results, or an appropriate result in the first three listings. Ask students what their experience of searching the Web is like, specifically. When they use Google, or another search engine, how do they determine which search results to click on. How many of the results from a search are valuable or appropriate? The text cites the example of searching for Paris Hilton versus Hilton in Paris. Both these searches produce similar results, because the computer does not understand the difference between these two concepts. In a more semantic Web, the difference would be understood. For “intelligent” computing, the text uses the example of using the Semantic web to set up and coordinate plans for a movie with a group of friends – changes to the plan would only take a few voice or text commands using a smartphone. Ask students what they think of these future visions of the Web.
• #24: This slide discusses the continuing revolution in wireless communication. Ask students to identify the wireless computing devices they use. (Cell phones, smart phones, PDAs, netbooks, laptops, ereaders, etc.) Ask students what changes or improvements have happened in their cell phone service over the past two years. Have they purchased or upgraded a cell phone in that time, and if so, why? How many students are using 3G phones? How many 4G? The next complete evolution in wireless communication, termed 4G, will be entirely packet-switched and capable of providing between 1 Mbps and 1 Gbps speeds, with premium quality and high security. 4G technologies currently include Long Term Evolution (LTE, Verizon), Ultra Mobile Broadband (UMB), and the mobile WiMax. Have students had any experience with these technologies?
• #25: This slide discusses the current standards in wireless networking. Ask students if they have any Bluetooth or wireless devices they use for computing. Many cars have Bluetooth support for cell phones. Note that in most Wi-Fi communications, wireless devices communicate with a wired LAN using an access point.
• #26: 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, cell phones, or PDAs.
• #27: 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.) The access point also controls the wireless stations.
• #28: 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). What are the potential benefits to WiMax – (broadband access in remote locations).
• #29: 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.
• #30: This slide continues the discussion of RFID technology. While the cost of RFID tags used to be too costly for widespread implementation, today the cost is about 10 cents for a passive tag, so RFID is becoming more cost-effective. Ask students why special hardware and software is needed to use RFID. (To filter, aggregate, and prevent RFID data from overloading business networks and system applications. ) Also, applications will need to be redesigned to accept massive volumes of frequently generated RFID data and to share those data with other applications. Major enterprise software vendors, including SAP and Oracle-PeopleSoft, now offer RFID-ready versions of their supply chain management applications.
• #31: This graphic illustrates how RFID works. Ask students if RFID poses any ethical problems.