7 - Telecom, internet & wireless tech

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7 - Telecom, internet & wireless tech

  1. 1. Chapter 7Telecommunications, the Internet, and Wireless Technology
  2. 2. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology LEARNING OBJECTIVES• Identify the principal components of telecommunications networks and key networking technologies.• Describe the main telecommunications transmission media and types of networks.• Explain how the Internet and Internet technology work and how they support communication and e-business.• Identify the principal technologies and standards for wireless networking, communication, and Internet access.• Assess the value to business of radio frequency identification (RFID) and wireless sensor networks.
  3. 3. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Virgin Megastores Keeps Spinning with Unified Communications• Problem: 1400 employees in 11 retail locations; slow resolutions of business issues because of cost of conference calls• Solutions: Implement unified communications to integrate voice mail, e-mail, conference calling, instant messaging• Microsoft’s Office Communication Server, Office Communicator, RoundTable conferencing and collaboration tools• Demonstrates IT’s role in hastening communication and flow of information
  4. 4. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World• Networking and communication trends • Convergence: • Telephone networks and computer networks converging into single digital network using Internet standards • Cable companies providing voice service • Broadband: • More than 60% of U.S. Internet users have broadband access • Broadband wireless: • Voice and data communication as well as Internet access are increasingly taking place over broadband wireless platforms
  5. 5. Components of data communication
  6. 6. What is Data ?• Data is a collection of facts, such as values or measurements.• It can be numbers, words, measurements, observations or even just descriptions of things.• Data can exist in a variety of forms -- as numbers or text on pieces of paper, as bits and bytes stored in electronic memory, or as facts stored in a persons mind.• Data is the plural of datum, a single piece of information.
  7. 7. DATA COMMUNICATION
  8. 8.  Data communication is the transfer of information between two points, either via an analogue (sine wave) electrical signal or digital (binary ) signal via electrical pulses or optically via light pulses. High speed data exchange between computers and/or other electronic devices via cable or wireless.
  9. 9. Data Transmission Modes There are three modes of transmitting data from one point to another. These are : Receiv• Simplex Sender er Sender Receiver• Half-duplex (or OR (or Receiver) Sender)• Full-duplex Sender Receiver (and AND (and Receiver) Sender)
  10. 10. COMPONENTS The main components of data communication system are:• Message• Sender• Receiver• Medium
  11. 11. MESSAGE• Message may exist in several different forms. It could be sound, light, picture, text, video etc.• A message is information which is sent from a source to a receiver.
  12. 12. TransmitterA transmitter is the agent, which could be ahuman or a machine, that actually wishes totransmit the data/ information to a recipient iscalled the transmitter or sender.
  13. 13. ReceiverReceiver is the component that collects the coded messagefrom the communication channel. This piece of data is still notin the form of the original message.
  14. 14. MediumOnce signal corresponding to the message is obtained, an end-to-end medium is required through which the signal may travelfrom the sender to the other end.
  15. 15. Transmission Medium• Provides the path for data communication.• Allows a bit stream to be transported from one machine to another.Twisted Pair CableCoaxial CableOptical Fiber Cable
  16. 16. MEDIA ADVANTAGES DISADVANTAGESTwisted Pair Inexpensive, well Sensitive to noise, Cables established. short distances, security hazard because of easy interception.Coaxial Cable High bandwidth, long Security is better in distances. comparison to twisted pair cable.Optical Fiber Very high bandwidth, long Connections Cost. Cable distances, high security, small size.
  17. 17. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World• What is a computer network? • Two or more connected computers • Major components in simple network • Client computer • Server computer • Network interfaces (NICs) • Connection medium • Network operating system • Hub or switch • Router
  18. 18. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business WorldComponents 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, cabling (wiring) connecting the devices, network interface cards (NIC), switches, and a router. Figure 7-1
  19. 19. What is a Computer Network? A network is a collection of computers, printers, routers, switches, and other devices that are able to communicate with each other over some transmission media.Types of Networks There are two basic types of networks currently in existence: A Local Area Network (LAN) A Wide Area Network (WAN)
  20. 20. Local AreaNetworks A Local Area Network (LAN) is a group of computers and(LAN) network communication devices within a limited geographic area, such as an office building. No third party involvement here. They are characterized by the following: • High data transfer speeds • Generally less expensive technologies • Limited geographic areaWide AreaNetworks(WAN) A Wide Area Network (WAN) interconnects LANs. It is not restricted to a particular geographic area and may be interconnected around the world. Third party network is involved. They are characterized by the following: • Multiple interconnected LANs • Generally more expensive technology • More sophisticated to implement than LANs • Exist in an unlimited geographic area • Less error resistance due to transmission travel distances
  21. 21. Common LAN Topologies Bus Architecture In a bus topology: • a single cable connects each workstation in a linear, daisy-chained fashion. •signals are broadcasted to all stations, but stations only act on the frames addressed to them. Ring Architecture •In a ring topology: •Unidirectional links connect the transmit side of one device to the receive side of another device. •Devices transmit frames to the next device (downstream member) in the ring.
  22. 22. Star Topology In a star topology, each station is connected to a central hub or concentrator that functions as a multi-port repeater. Each station broadcasts to all of the devices connected to the hub. Physical LAN topologies are usually characterized as either bus or ring.
  23. 23. LAN Transmission Methods LAN transmission methods fall into 3 main categories: • Unicast transmission • Multicast transmission • Broadcast transmissionUnicast Transmission In unicast transmissions, a single data packet is sent from a source to a single destination on the network. Unicast Process • The source addresses the packet with the destination address. • The packet is sent into the network. • The network delivers the packet to the destination.
  24. 24. Multicast Transmission In multicast transmissions, a single data packet is copied and sent to specific destinations on the networkMulticast Process• The source addresses the packet using a multicast address.• The packet is sent into the network.• The network copies the packet.• A copy is delivered to each destination that is included in the multicast address.Broadcast Tranmission In Broadcast transmissions, a single data packet is copied and sent to all destinations on the network
  25. 25. Broadcast Process• The source addresses the packet with the broadcast address.• The packet is sent into the network.• The network copies the packet.• The packet copies are delivered to all destinations on the network.
  26. 26. Uses of Computer Networks• Resource Sharing: Many organizations have large number of substantial computers in operation often located far apart. Let us consider an example, a company having many factories situated at different locations. A computer at each location (that is in each factory) keeps the track of inventories, monitor productivity and do the local pay roll. Initially each of these computers may have worked in isolation from each other, but at some point, the management may have decided to connect these computers to be able to extract and correlate the information of the entire company. The issue here is resource sharing. Its goal is to make all the programs, equipments, especially data available to anyone on the network irrespective of the location of the resource and the user.
  27. 27. • High Reliability: The second goal or use of networking in companies is to high reliability by having alternative sources of supply. For example all the files can be replicated on two or more machines, so that in case one of them is not available (due to hardware failure), other copies can be used. This feature is used in financial institutions.• Scalability: Another goal is scalability. Scalability is the ability to increase the system performance gradually as the workload grows, by just adding more processors.
  28. 28. • Saving Money: The third goal is to save money. Small computers often have better price/performance ratio than the larger ones. Mainframe (room-size) computers are roughly ten times faster than the personal computers, but are a thousand times costly. This imbalance caused the system designers to design a system consisting of personal computers, one per user, with data kept on one or more shared file server machines. In this model the user are called the clients and this whole arrangement is known as the client-server model. In client-server model, the communication generally takes the form of a request message from a client to the receiver asking for some work to be done. Server does the work and sends back the reply.
  29. 29. • Access to Remote Information: Access to remote information occurs in many forms. One of the areas where it is happening is access to the financial institutions. Many people pay their bills, manage bank accounts and handle investments electronically. Home shopping is also becoming popular these days. Another application that falls under this category is the access to information systems like World Wide Web which contains information about art, business, history, government, geography, economics and several other topics. All the above applications involve the interaction between the user and a remote database.
  30. 30. • Person to Person Communication: Electronic Mail popularly known as email is widely used by millions of people to send text messages, photographs audio as well as video to other people or group of people. This application belongs to person to person communication category. Videoconferencing is also becoming popular these days. This technology makes it possible to have virtual meetings among far flung people. It is also a type of person to person communication.
  31. 31. • Interactive Entertainment: These days we can see many live programmes and shows. The best thing is that we can interact with them by participating in the quizzes and the contests organized by them.• File sharing: Have you ever needed to access a file stored on another computer? A network makes it easy for everyone to access the same file and prevents people from accidentally creating different versions.
  32. 32. • Printer sharing: If you use a computer, chances are you also use a printer. With a network, several computers can share the same printer. Although you might need a more expensive printer to handle the added workload, its still cheaper to use a network printer than to connect a separate printer to every computer in your office.• Communication and collaboration: Its hard for people to work together if no one knows what anyone else is doing. A network allows employees to share files, view other peoples work, and exchange ideas more efficiently. In a larger office, you can use e-mail and instant messaging tools to communicate quickly and to store messages for future reference.
  33. 33. • Organization: A variety of scheduling software is available that makes it possible to arrange meetings without constantly checking everyones schedules. This software usually includes other helpful features, such as shared address books and to-do lists.
  34. 34. Networking Hardware• NICs• Repeaters and Hubs• Switches• Routers• Bridges• Brouter• Gateway• Modems• ISDN Adaptors• CSU/DSU• Network Example
  35. 35. NICs• Network interface cards (also called NICs, network adapters, LAN Card or network cards) are connectivity devices that enable a workstation, server, printer, or other node to receive and transmit data over the network media.• Nearly all NICs contain a data transceiver, the device that transmits and receives data signals.• NICs belong to both the Physical layer and Data Link layer of the OSI Model, because they apply data signals to the wire and assemble or disassemble data frames.• In addition, they perform the routines that determine which node has the right to transmit data over a network at any given instant
  36. 36. Repeaters and Hubs• Repeaters operate in the Physical layer of the OSI Model and, therefore, have no means to interpret the data they retransmit.• They simply regenerate a signal over an entire segment.• A repeater contains one input port and one output port, so it is capable only of receiving and repeating a data stream• Repeaters are suited only to bus topology networks• The advantage to using a repeater is that it allows you to extend a network inexpensively
  37. 37. Repeaters and Hubs• A hub is a repeater with more than one output port.• A hub typically contains multiple data ports into which the patch cables for network nodes are connected.• A hub accepts signals from a transmitting node and repeats those signals to all other connected nodes in a broadcast fashion
  38. 38. Switches• Switches are connectivity devices that subdivide a network into smaller logical pieces, or segments.• Switches operate at the Data Link layer of the OSI Model, while more modern switches can operate at Layer 3 or even Layer 4.• Switches interpret MAC address information
  39. 39. • Because they have multiple ports, switches can make better use of limited bandwidth.• Each device connected to a switch effectively receives its own dedicated channel to the switch.• From the Ethernet perspective, each dedicated channel represents a collision domain.• Because a switch limits the number of devices in a collision domain, it limits the potential for collisions.• By their nature switches provide better security than many other devices because they isolate one devices traffic from other device’s traffic
  40. 40. • Connecting a workstation to a switch
  41. 41. • A switch on a small network
  42. 42. Switches Contd….• Switches differ in the method of switching they use: 1. Cut-through mode 2. Store and forward modeCut-Through Mode• A switch running in cut-through mode reads a frames header and decides where to forward the data before it receives the entire packet.• What if the frame becomes corrupt? Because the cut- through mode does not allow the switch to read the frame check sequence (FCS) before it begins transmitting, it cant verify data integrity in that way.
  43. 43. Store and Forward Mode• In store and forward mode, a switch reads the entire data frame into its memory and checks it for accuracy before transmitting the information.• Although this method is more time-consuming than the cut- through method, it allows store and forward switches to transmit data more accurately.• Store and forward mode switches are more appropriate for larger LAN environments, because they do not propagate data errors.
  44. 44. Routers• A router is a multiport connectivity device that directs data between nodes on a network.• Routers can integrate LANs and WANs running at different transmission speeds and using a variety of protocols.• When a router receives an incoming packet, it reads the packets logical addressing information. – Based on this, it determines to which network the packet must be delivered. – Then it determines the shortest path to that network. – Finally it forwards the packet to the next hop in that path.
  45. 45. • A routers strength lies in its intelligence.• Not only can routers keep track of the locations of certain nodes on the network, as switches can, but they can also determine the shortest, fastest path between two nodes.• For this reason, and because they can connect dissimilar network types, routers are powerful, indispensable devices on large LANs and WANs.• The Internet, for example, relies on a multitude of routers across the world
  46. 46. • A typical router has an internal processor, an operating system, memory, input and output jacks for different types of network connectors (depending on the network type), and, usually, a management console interface.
  47. 47. Hub versus Switch• Hub provide connection to all ports (i.e. in one port and out all other ports). – Passive hub – no signal regeneration – Active hub – provide signal regeneration• Switch direct the message from appropriate port (directs a message from the input port to the desired output port). – More expensive but better bandwidth utilization
  48. 48. Hub versus Switch
  49. 49. Bridge• Connects two LAN segments to make one larger continuous LAN• Filters LAN traffic to keep local traffic.• Allows connectivity to other parts of the LAN• Simple to install and manage—costs less than router• Checks MAC address to make forwarding decisions• Considered layer 2 device
  50. 50. Bridge – Access Point (WLAN)
  51. 51. Brouter• Network bridge and router combined together to form a device known as brouter.
  52. 52. Gateway• A gateway is a network point that acts as an entrance to another network. On the Internet, a node or stopping point can be either a gateway node or a host (end-point) node. Both the computers of Internet users and the computers that serve pages to users are host nodes, while the nodes that connect the networks in between are gateways. For example, the computers that control traffic between company networks or the computers used by internet service providers (ISPs) to connect users to the internet are gateway nodes.• In the network for an enterprise, a computer server acting as a gateway node is often also acting as a proxy server and a firewall server. A gateway is often associated with both a router, which knows where to direct a given packet of data that arrives at the gateway, and a switch, which furnishes the actual path in and out of the gateway for a given packet.
  53. 53. Modem• Allows modems of different vendors to operate together• Define How modems operate: – Modulation techniques – Data compression technique – Error detection strategy – Parallel to Serial and vice versa
  54. 54. • Analog – Infinite number of levels – Conform to voice pattern – Times from highest to lowest and back to the highest point in one second is the frequency – Can be transmitted over long distance• Digital – Only two levels (high and low) – Conforms to how computers operate – Cannot transmitted over long distance
  55. 55. Modem - Connection
  56. 56. Modem – Internal/External
  57. 57. ISDN Adaptors• ISDN (Integrated Services Digital Network) is a data communication method and it is used over the regular telephone lines. To use the ISDN lines, you need to install add-on adapters known as ISDN terminal adapters. ISDN Terminal Adapter works like a digital modem i.e. it converts the signals from digital to analog and vice versa. ISDN Terminal adapter is plugged into the serial port of the system. Some ISDN adapters have the feature of switching between digital and analog modes.
  58. 58. CSU/DSU• CSU/DSU stands for channel service unit and data service unit. CSU is used to connect a terminal to a digital line. DSU is used to perform the protective and diagnostic functions of the telecommunication line. CSU/DSU is a network device of the size of an external modem. The Channel service unit receives and transmits the signals from the wide area network line. CSU/DSU are two separate devices and they are sometimes used in conjunction with the T1 LAN cards.
  59. 59. Network Example
  60. 60. Network Software• Network Software is a set of primitives that define the protocol between two machines. The network software resolves an ambiguity among different types of network making it possible for all the machines in the network to connect and communicate with one another and share information.• Network software is the information, data or programming used to make it possible for computers to communicate or connect to one another.• Network software is used to efficiently share information among computers. It encloses the information to be sent in a “package” that contains a “header” and a “trailer”. The header and trailer contain information for the receiving computer, such as the address of that computer and how the information package is coded. Information is transferred between computers as either electrical signals in electric wires, as light signals in fiber-optic cables, or as electromagnetic waves through space.
  61. 61. Networks provide computer users aconvenient way to transfer files acrossdata connections. Secured networksrequire a user name and password inorder to connect your computer to thenetwork. Unsecured networks do notneed any authentication. All types ofnetworks need software to interface withthe network and begin communicationand data transfer.
  62. 62. • Home Software : Setting up a network using the Cisco software Network Magic Pro is easy; the software was programmed with novice computer users in mind. Tasks such as creating secured Internet connections, sharing digital devices such as cameras and printers and monitoring Web access are all controlled through the softwares main interface. This software is ideal for entry-level computer users.• Free Software : Spiceworks provides a budget-friendly option for individuals who want a network management software package. The software is free and offers many of the same features as other software packages available for sale. This software package was intended to be used within small to medium sized businesses. The few of the key features are the ability to inventory everything on your network, run an IT Helpdesk and Map the Network.
  63. 63. • Monitoring Tools : Networks are often damaged from burnt power supplies, servers crashing, low bandwidth and even attacks from computer hackers. Computer hackers are experts in network administration, but the appropriate software will stop hackers dead in their tracks. The software Monitor Tools provides a central location to monitor and maintain all these potential trouble spots. The software will tell you of possible system issues and provide quick suggestions for the resolution of each problem as it arises.• Application Performance : Network administrators are sometimes charged with the sole task of monitoring application performance, for example, making sure that files are sent immediately and are successfully delivered on the receiving end. Orion APM is a software package that focuses exclusively on application monitoring, ensuring all network systems are running as quickly as possible.
  64. 64. • Warning : Choosing to set up a security system for your wireless network is a decision to be taken seriously. A wireless network places your computer files at the fingertips of anyone within the broadcast range of your wireless router. Personal information such as Social Security numbers and credit cards should always be stored behind the protection of certified network security software. Once your network is set up, and your files are secured, routine backups of any important files should be created onto hard drives, DVDs or other external storage medium. The only way to be absolutely certain your files are safe is to have a hard copy stored outside the network; if the network fails and data is lost, you will be certain your important files are still safe.
  65. 65. Network Model Overview In order for a computer to send information to another computer, and for that computer to receive and understand the information, there has to exist a set of rules or standards for this communication process. These standards ensure that varying devices and products can communicate with each other over any network. This set of standards is called a model.Network Model Advantages This division provides advantages for the network design, architecture and implementation. These include: Reduces complexity - by dividing the processes into groups, or layers, implementation of network architecture is less complex •Provides compatibility - standardized interfaces allow for "plug-and-play" compatibility and multi-vendor integration •Facilitates modularization - developers "swap" out new technologies at each layer keeping the integrity of the network architecture •Accelerates evolution of technology - developers focus on technology at one layer while preventing the changes from affecting another layer •Simplifies learning - processes broken up into groups divides the complexities into smaller, manageable chunks
  66. 66. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World• Networks in large companies• Components can include: • Hundreds of local area networks (LANs) linked to firmwide corporate network • Various powerful servers • Web site • Corporate intranet, extranet • Backend systems • Mobile wireless LANs (Wi-Fi networks) • Videoconferencing system • Telephone network • Wireless cell phones
  67. 67. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World Corporate Network InfrastructureFigure 7-2Today’s corporate networkinfrastructure is a collection ofmany different networks from thepublic switched telephonenetwork, to the Internet, tocorporate local area networkslinking workgroups, departments,or office floors.
  68. 68. 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 • Distributed computing model • Clients linked through network controlled by network server computer • Server sets rules of communication for network and provides every client with an address so others can find it on the network • Has largely replaced centralized mainframe computing • The Internet: Largest implementation of client/server computing
  69. 69. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World• Packet switching • Method of slicing digital messages into parcels (packets), sending packets along different communication paths as they become available, and then reassembling packets at destination • Previous circuit-switched networks required assembly of complete point-to-point circuit • Packet switching more efficient use of network’s communications capacity
  70. 70. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World Packet-Switched Networks and Packet CommunicationsFigure 7-3Data are grouped into small packets,which are transmitted independently overvarious Communications channels andreassembled at their final destination.
  71. 71. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World• TCP/IP and connectivity • Connectivity between computers enabled by protocols • Protocols: Rules that govern transmission of information between two points • Transmission Control Protocol/Internet Protocol (TCP/IP) • Common worldwide standard that is basis for Internet • Department of Defense reference model for TCP/IP • Four layers • Application layer • Transport layer • Internet layer • Network interface layer
  72. 72. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Telecommunications and Networking in Today’s Business World The Transmission Control Protocol/Internet Protocol (TCP/IP) Reference ModelFigure 7-4This figure illustrates the four layers of theTCP/IP reference model for communications.
  73. 73. OSI Network Model There are 7 layers in the OSI model. Each layer is responsible for a particular aspect of data communication. For example, one layer may be responsible for establishing connections between devices, while another layer may be responsible for error checking during transfer. The layers of the OSI model are divided into two groups: the upper layer and lower layer. The upper layers focus on user applications and how files are represented on the computers prior to transport. For the most part, network engineers are more concerned with the lower layers. Its the lower layers that concentrate on how the communication across a network actually occurs. ALL People Seem to Need Data Processing (Layer 7 to 1) Please Do Not Take Sausage Pizzas Away (Layer 1 to 7)
  74. 74. The Application Layer The Application Layer is the highest layer in the protocol stack and the layer responsible for introducing data into the OSI stack. In it resides the protocols for user applications that incorporate the components of network applications. Classification of Applications Computer applications Network applications Internetwork applications Examples: Telnet, FTP, HTTP, WWW Browsers, NFS, SMTP, POP, TFTP .
  75. 75. Presentation Layer The Presentation Layer manipulates the representation of data for transfer to applications on different devices. The Presentation Layer is responsible for the following services: • Data representation • Data security • Data compression Data Representation
  76. 76. Session Layer The Session Layer establishes, manages, and terminates sessions (different from connections) between applications as they interact on different hosts on a network. Its main job is to coordinate the service requests and responses between different hosts for applications. Examples: NFS, SQL, RPC, ASP Three different communication modes exists for data transfer within a session connection: • Single-duplex• Half-duplex• Full-duplex.
  77. 77. Figure 2.1 Tasks involved in sending a letter 2.80
  78. 78. What do the 7 layers really do?
  79. 79. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks• Signals: digital vs. analog • Modem: Translates digital signals into analog form• Types of networks • Local-area networks (LANs) • Client/server or peer-to-peer • Ethernet – physical network standard • Topologies: star, bus, ring • Campus-area networks (CANs) • Wide-area networks (WANs) • Metropolitan-area networks (MANs)
  80. 80. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks Functions of the ModemA modem is a device that translates digital signals from a computer into analog form so that they can be transmitted overanalog telephone lines. The modem also translates analog signals back into digital form for the receiving computer. Figure 7-5
  81. 81. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks Network TopologiesFigure 7-6The three basic networktopologies are the bus,star, and ring.
  82. 82. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks• Physical transmission media • Twisted wire (modems) • Coaxial cable • Fiber optics and optical networks• Wireless transmission media and devices • Microwave • Satellites • Cellular telephones• Transmission speed • Hertz • Bandwidth
  83. 83. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology Communications Networks BP Amoco’s Satellite Transmission SystemFigure 7-7Communication satelliteshelp BP Amoco transferseismic data between oilexploration ships andresearch centers in theUnited States.
  84. 84. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet• What is the Internet?• Connecting to the Internet • Internet service providers (ISPs) • Services • DSL, cable, satellite, T lines (T1, T3)• Internet addressing and architecture • IP addresses • The domain name system • Hierarchical structure • Top-level domains
  85. 85. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet The Domain Name SystemFigure 7-8The Domain Name System is ahierarchical system with a rootdomain, top-level domains,second-level domains, and hostcomputers at the third level.
  86. 86. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet• Internet Architecture • Trunk lines (backbone networks) • Regional networks • ISPs• Internet Governance • No formal management • Policies established by professional, government organizations • IAB, ICANN, W3C• The Future Internet • IPv6 • Internet2, NGI
  87. 87. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet Internet Network ArchitectureFigure 7-9The Internet backbone connectsto regional networks, which inturn provide access to Internetservice providers, large firms,and government institutions.Network access points (NAPs)and metropolitan areaexchanges (MAEs) are hubswhere the backbone intersectsregional and local networks andwhere backbone owners connectwith one another.
  88. 88. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution Should Network Neutrality Continue?• Read the Interactive Session: Organization and then discuss the following questions: • What is network neutrality? Why has the Internet operated under net neutrality up to this point in time? • Who’s in favor of network neutrality? Who’s opposed? Why? • What would be the impact on individual users, businesses, and government if Internet providers switched to a tiered service model? • Are you in favor of legislation enforcing network neutrality? Why or why not?
  89. 89. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet• Internet services • E-mail • Chatting and instant messaging • Newsgroups • Telnet • File Transfer Protocol (FTP) • World Wide Web• Voice over IP (VoIP)• Unified communications• Virtual private networks (VPNs)
  90. 90. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet Client/Server Computing on the InternetFigure 7-10Client computers running Webbrowser and other software canaccess an array of services on serversover the Internet. These services mayall run on a single server or onmultiple specialized servers.
  91. 91. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global InternetMonitoring Employees on Networks: Unethical or Good Business? • Read the Interactive Session: Management and then discuss the following questions: • Should managers monitor employee e-mail and Internet usage? Why or why not? • Describe an effective e-mail and Web use policy for a company.
  92. 92. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet How Voice over IP WorksAn VoIP phone call digitizes and breaks up a voice message into data packets that may travel along different routes beforebeing reassembled at the final destination. A processor nearest the call’s destination, called a gateway, arranges the packetsin the proper order and directs them to the telephone number of the receiver or the IP address of the receiving computer. Figure 7-11
  93. 93. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet A Virtual Private Network Using the InternetThis VPN is a private network of computers linked using a secure “tunnel” connection over the Internet. It protects data transmittedover the public Internet by encoding the data and “wrapping” them within the Internet Protocol (IP). By adding a wrapper around anetwork message to hide its content, organizations can create a private connection that travels through the public Internet. Figure 7-12
  94. 94. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet• The World Wide Web • HTML (Hypertext Markup Language): • Formats documents for display on Web • Hypertext Transfer Protocol (HTTP): • Communications standard used for transferring Web pages • Uniform resource locators (URLs): • Addresses of Web pages • E.g., http://www.megacorp.com/content/features/082602.html • Web servers • Software for locating and managing Web pages
  95. 95. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet• Search engines • Started in early 1990s as relatively simple software programs using keyword indexes • Today, major source of Internet advertising revenue via search engine marketing, using complex algorithms and page ranking techniques to locate results • Sponsored links vs. organic search results• Shopping bots • Use intelligent agent software for searching Internet for shopping information
  96. 96. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet How Google WorksFigure 7-13The Google search engine iscontinuously crawling theWeb, indexing the content ofeach page, calculating itspopularity, and storing thepages so that it can respondquickly to user requests tosee a page. The entireprocess takes about one-halfsecond.
  97. 97. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet Major Web Search EnginesFigure 7-14Google is the most popular searchengine on the Web, handling 56 percentof all Web searches.
  98. 98. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet• Web 2.0 • Second-generation interactive Internet-based services enabling people to collaborate, share information, and create new services online • Cloud computing • Software mashups and widgets • Blogs: Chronological, informal Web sites created by individuals using easy-to-use weblog publishing tools • RSS (Really Simple Syndication): Syndicates Web content so aggregator software can pull content for use in another setting or viewing later • Wikis: Collaborative Web sites where visitors can add, delete, or modify content on the site
  99. 99. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet• Web 3.0 • Current efforts to make using Web more productive • Inefficiency of current search engines: Of 330 million search engine queries daily, how many are fruitful? • Semantic Web • Collaborative effort to add layer of meaning on top of Web, to reduce the amount of human involvement in searching for and processing Web information • Other, more modest views of future Web • Increase in cloud computing, SaaS • Ubiquitous connectivity between mobile and other access devices • Make Web a more seamless experience
  100. 100. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Global Internet• Intranets • Use existing network infrastructure with Internet connectivity standards software developed for the Web • Create networked applications that can run on many types of computers • Protected by firewalls• Extranets • Allow authorized vendors and customers access to an internal intranet • Used for collaboration • Also subject to firewall protection
  101. 101. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution• Wireless devices • PDAs, BlackBerry, smart phones• Cellular systems • Competing standards for cellular service • United States: CDMA • Most of rest of world: GSM • Third-generation (3G) networks • Higher transmission speeds suitable for broadband Internet access
  102. 102. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution• Wireless computer networks and Internet access • Bluetooth (802.15) • Links up to 8 devices in 10-m area using low-power, radio- based communication • Useful for personal networking (PANs) • Wi-Fi (802.11) • Set of standards: 802.11a, 802.11b, 802.11g, 802.11n • Used for wireless LAN and wireless Internet access • Use access points: Device with radio receiver/transmitter for connecting wireless devices to a wired LAN
  103. 103. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution A Bluetooth Network (PAN)Figure 7-15Bluetooth enables a varietyof devices, including cellphones, PDAs, wirelesskeyboards and mice, PCs,and printers, to interactwirelessly with each otherwithin a small 30-foot (10-meter) area. In addition tothe links shown, Bluetoothcan be used to networksimilar devices to send datafrom one PC to another, forexample.
  104. 104. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution An 802.11 Wireless LANFigure 7-16Mobile laptop computers equipped withwireless network interface cards link tothe wired LAN by communicating withthe access point. The access point usesradio waves to transmit network signalsfrom the wired network to the clientadapters, which convert them into datathat the mobile device can understand.The client adapter then transmits thedata from the mobile device back to theaccess point, which forwards the datato the wired network.
  105. 105. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution• Wireless computer networks and Internet access • Wi-Fi (cont.) • Hotspots: One or more access points in public place to provide maximum wireless coverage for a specific area • Weak security features • WiMax (802.16) • Wireless access range of 31 miles • Require WiMax antennas • Sprint Nextel building WiMax network
  106. 106. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution• Radio frequency identification (RFID) • Use tiny tags with embedded microchips containing data about an item and location, and antenna • Tags transmit radio signals over short distances to special RFID readers, which send data over network to computer for processing • Active RFID: Tags have batteries, data can be rewritten, range is hundreds of feet, more expensive • Passive RFID: Range is shorter, also smaller, less expensive, powered by radio frequency energy
  107. 107. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution• Radio frequency identification (RFID) • Common uses: • Automated toll-collection • Tracking goods in a supply chain • Requires companies to have special hardware and software • Reduction in cost of tags making RFID viable for many firms
  108. 108. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution How RFID WorksRFID uses low-powered radio transmitters toread data stored in a tag at distances rangingfrom 1 inch to 100 feet. The reader captures thedata from the tag and sends them over anetwork to a host computer for processing. Figure 7-17
  109. 109. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution• Wireless sensor networks • Networks of hundreds or thousands of interconnected wireless devices embedded into physical environment to provide measurements of many points over large spaces • Used to monitor building security, detect hazardous substances in air, monitor environmental changes, traffic, or military activity • Devices have built-in processing, storage, and radio frequency sensors and antennas • Require low-power, long-lasting batteries and ability to endure in the field without maintenance
  110. 110. Management Information Systems Chapter 7 Telecommunications, the Internet, and Wireless Technology The Wireless Revolution A Wireless Sensor NetworkFigure 7-18The small circles representlower-level nodes and the largercircles represent high-endnodes. Lower-level nodesforward data to each other or tohigher-level nodes, whichtransmit data more rapidly andspeed up network performance.

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