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									   PENGANTAR APLIKASI KOMPUTER


DISUSUN OLEH :
  1. Retno Larasati (01091001007)
  2. Rezti Yulanda (01091001005)
  3. Yulis Hari Yana (01091001011)




                                     BAB 8
         TELECOMUNICATIONS AND NETWORKS

  1. What us the significance of telecommunications deregulation for managers and
     organizations?
     Answer :Thousand of companies have sprung up to provide telecommunications
     products and service., data networks, cable TV, communications satellites, and
     internet services. Managers are continually faced with decisions on how to
     incorporate these services and technologies into their information system and
     business processes


  2. What is telecommunications system? What are the principal functions of all
     telecommunications system?
     Answer : a telecommunications system is a collection of compatible hardware and
     software arranged to communicate information from one location to another.


  3. Name and briefly describe each of the components of a telecommunications
     system.
     Answer : Components of a telecommunications system. This figure illustrates
     some of the hardware components that would be found in a typical
     telecommunications system. They include computers, terminals, communications
   channels. And communications processor, such as modem . multiplexers , and the
   front- end processor. Special communoications software controls input and output
   activities and manages other functions of the communications system.


4. Distinguish between ab analog and digital signal.
   Answer : An analog signal is represented by continous waveform that passes
   through a communications medium. Analog signal are used to handle voice
   communications and to reflect variations in pitch. A digital signal is a discrete,
   rather than a continous, wavefrom. It transmits data pulses.


5. Name the different types of telecommunications transmission media and compare
   them in terms of speed and cost.
   Answer : A channel can use differents kinds of telecommunications transmissions
   media : twisted wire, coaxial cable, fiber optics, terrestrial microwave, satellite,
   and other wireless transmissions. Each as advantages and limitations. High speed
   transmissions media are more expensive in general, but they can handle higher
   volumes, which reduces the cost per bit.


6. Name and describe the technologies used for wireless transmission.
   Answer : Wireless transmissions that signals through air or space without any
   physical tether has become an increasingly popular alternative to tethered
   transmission channels such as twisted wire, coaxial cable, and fiber optics. The
   wireless transmissions medium is the electromagnetic spectrum. Some types of
   wireless transmissions, such as microwave or infared.


7. What are optical networks ? Why are they becoming important?
   Answer : Optical networks is networking technologies for transmitting data in the
   form of light pulses. These optical networks can transmit all types of traffic-
   voice, data, and video- over fiber cables and provide the mssive bandwidth for
   new types of services and software
8. What is the relayionship between bandwidth and a channel’s transmissions
   capacity?
   Answer: The range of frequencies that can be accomadated on a single channel.
   The greater the range of frequencies, the greater the bandwidth and the greater the
   channel’s transmissions capacity.


9. Name and briefly describe the different kinds of communications processor.
   Answer : Communications processors, the front-end processor is a special-
   purpose computer dedicated to communications managements and is attached to
   the main, or host, computer. A concentrator is a programmable telecommunica
   tions computer that collects and temporarily stores messages from terminals until
   enough messages are ready to be sent economically. A controller is a specialized
   computer that supervises communications traffic between the CPU and peripheral
   devices such as terminals and printers. A multiplexer is a device that enables a
   single communications channel to carry data transmissions from multiple sources
   simultaneously.


10. Name and briefly describe the three principal networks topologies.
   Answer : 1. The star networks, consist of a central host computer connected to a
   number of smaller computers. Thois topology is useful for applications where
   some processing must be centralized and some can be performed locally. 2. The
   bus network, links a number of a computers by a single circuit made of twisted
   wire, coaxial cable, or fiber- optic cable.All of the signals are broadcast in both
   directions to the entire networks, with special software to identify which
   components receive each message (there is no central host computer to control the
   network). 3. The ring network, does not rely on a central host computer and will
   not necessarily break down if one of the component computers malfunctions


11. Distinguish between a PBX and a LAN.
   Answer : A private branch exchange (PBX) is a special- purpose computers
   designed for handling and switching office telephone calls at a company site.
   PBXs can store, transfer, hold, and redial telephone calls, and they also can be
   used to switch digital information among computers and office devices. The
   advantages of digital PBXs over other local networking options is that they do not
   require special wiring. A Local Area Network (LAN) encompasses a limited
   distance, usually one building or several buildings in close proximity. LANs
   require their own communications channels. LANs are more expensive to install
   than PBXs and are more inflexible, requiring new wiring each time a LAN is
   moved.


12. What are the components of typical LAN ? What are the functions of of the
   components?
   Answer : Components of typical LAN is : A gateway is generally a
   communications processor that can connect dissimilar networks by translating
   from one set of protocols to another. A router is used to route packets of data and
   to determine the next point in a networks to witch the data should be sent. LAN
   capabilities also are defined by the networks operating system (NOS). The
   network operating system can reside on every computer in the networks,or it can
   reside on a single designated server for all the applications on the network.A peer-
   to-peer network treats all processor equally and is used primarily in small
   networks


13. List and describe the various networks services.
   Answer : Networks services
    Service                Descriptions                     Bandwidth
    X.25                   Packet- switching standard Up to 1.544 MBPS
                           that   parcels   data     info
                           packets of 128 bytes
    Frame relay            Packages data info frames Up to 1.544 MBPS
                           for      high-          speeed
                           transmissions over reliable
                           lines but does not use error-
                        corrections routines
    ATM                 Parcels data info uniform 25 MBPS-2.5 GBPS
    (asynchronous       cells to allow high-capacity
    transfer mode)      transmissions of voice, data,
                        images, and video between
                        different types of computers
    ISDN                Digital   dial-up      network Basic     Rate   ISDN      :128
                        access standard that can KBPS
                        integrate voice, data, and Primary Rate ISDN : 1.5
                        video services                   MBPS
    DSL          (digital Series of technologies for ADSL-up to 9 MBPS for
    subscriber line)    high-capacity transmissions receiving and up to 640
                        over copper wires                KBPS for sending data;
                                                         SDSl-up to 3 MBPS for
                                                         both sending and receiving
    T1                  Deducated           telephone 1.544 MBPS
                        connection       with      24
                        channels for high- capacity
                        transmission
    Cable modem         Service for high- speed Up to 4 MBPS
                        transmissions of data over
                        cable TV lines that shared
                        by many users


14. Distinguish between a WAN and a VAN.
   Answer : Wide Area Networks (WAN) span broad geographical distances,
   ranging from several miles to entire cintinents. WANs may consist of a
   combination of switched and dedicated lines, microwave, and satelllte
   communications.Value-added Networks (VANs)           are private, multipath, data-
   omly, third- party managed networks that can provide economies in the cost of
   service and in network managements because they are used by multiple
   organizations


15. Define the following ; modem, baud, protocol, converged network, and
   broadband.
   Answer: Modem os a device for translating digital signals into analog signals and
   vice versa. Baud is a change in signal from positive to negative or vice versa that
   is used as a measure of transmissions speed. Protocol is a set of rules and
   procedures that govern transmissions between the components in a network.
   Converged nework is network with technology to enable voice and data to run
   over a single network. Broadband is high- speed transmissions technology. Also
   designates a communications medium that can transmit multiple channels of data
   simultaneously


16. Name and describe the telecommunications applications that can support
   electronic commerce and electronic business.
   Answer : Customers could dial up a local VAN and send their orders directly to
   the company . Other companies also are archieving strategic benefits by
   developing electronic commerce and electronic business applications based on
   networking technologies.




                                    BAB 9
   THE INTERNET AND THE NEW INFORMATION
            TECHNOLOGY INFRASTRUCTURE

1. What are the features of the new information technology (IT) infrastructure?
   Answer : The new information technology (IT) infrastructure ; The new IT
   infrastructure links, desktop workstations, network computers, LANs, and server
   computers in an enterprise network so that information can flow freely between
         parts of the organization. The enterprise network may also be linked to kiosks,
         point-of-sale (POS) terminals, PDAs and information appliances, digital cellular
         telephones and PCS, and mobile computing devices as well as to the internet
         using public infrastructure, customers, supplier, and business partners may also be
         linked to the organization through this new IT infrastructure.


   2. Why is connectivity so important for the digital firm? List and describe the major
         connectivity standards for networking and the internet.
         Answer : Today’s firm can use the information technologies we have described in
         previous chapters to create an information technology (IT) infrastructure capable
         of coordinating the activities of entire firms and even entire industries. By
         enabling companies to radically reduce their agency and transaction costs, this
         new IT infrastructure provides a broad platform for electronic commerce,
         electronic business, and the emerging digital firm. This new IT infrastructure is
         based on powerful networks and internet technology


   3. what is the internet ? List and describe alternative ways of accesing the internet.
         Answer : The intrenet is perhaps the most well-known, and the largest,
         implementation of internet working, linking hundreds of thousanda of individual
         networks all over the world. Internet Service Provider (ISP)is commercial
         organization with a permanent connection to the internet that sells temporary
         connections to subscribes. Individuals also can accsess the internet through such
         popular on-line services as prodigy and America online and through networks
         established by such giant as Microsoft and AT & T


   4. List and describe the principal internet capabilities.
         Answer : major internet services
Capability                         Functions Supported
E-mail                             Person to person messaging; document sharing
Usenet newsgropu                   Discussions groups on electronic bulletin boards
LISTSERVs                          Discussions groups and messaging using e-mail mailing
                                     list servers
Chatting                             Interactive conversations
Telner                               Log on to one computer to computer
Gophers                              Locate information using a hierarchy of menus
World Wide web                       Retrieve, format, and display information (including
                                     text, audio, graphics, and video) using hypertext links
   5. What is internet2 ? How does it differ from the first generation internet? What
         benefits does it provide?
         Answer : Internet2 is a research network with new protocols and transmissions
         speeds that are much higher than the current internet. The intenet2 infrastructure
         is based on a series of interconnected gigaPoPs, which are regional high- speed
         points-of-presence that serve as aggregation points for traffic from participating
         institututions.


   6. why is the World Wide Web so useful for individuals and business?
         Answer : The World Wide Web (The web) is at the heart of the exlosion in the
         business use of the Net. The web is a system with universally accepted standards
         for storing, retrieving, foemating, and displaying information using a client/
         server architecture. The web combines text, hypermedia, graphics, and sound. It
         can handle all types of digital communication, making it easy to link resources
         that are half-a-world apart. The web use graphical use interfaces for easy viewing.
         It is based on a standards hypertext language called hypertext markup language
         (HTML), which formats documents and incorporates dynamic links to other
         documents stored in the same or remote computers.


   7. list and describe alternative ways of locating information on the web.
         Answer : locating information on the web is a critical function, with the more than
         one billion Web pages in existence expented to double in eight months. No
         comprehensive catalog of web sites exists. The principal methods of locating
         information on the web are web site directories, search engines, and broadcast or
         “push” technology.
8. What are intranets and extranets? How do they differ from the web?
   Answer : organizations can use internet networking standards and web technology
   to create private networks called intranets. Some firms are allowing people and
   organizations outside the firm to have limited accsess to their internal intranets.
   Private intranets that are extended to authorized users outside the company are
   called extranets


9. what is the wireless web ? How does it differ from the conventional Web ?
   Answer : Wireless web is web-based applications enabling users to access digital
   information from the internet using wireless mobile computing devices


10. list and describe the types of m-commerce services and applications supported by
   the wireless web.
   Answer : M-commerce, the use of the internet for purchasing goods and services
   as well as sending and receiving messages using handled wireless devices. With
   cell phones, PDAs, and other wireless computing devices becoming Internet-
   enabled, many believe m-commerce represents the next wave of internet
   computing. M-commerce will become a significabt subset of e-commerce.
   Business will increasingly incorporate wireless internet accsess into their
   information technology infrastructures so that employess can access information
   wherever thay are, and make decisions instantly without being tethered to a desk
   or computer. Wireless web applications enable mobile users to access digital
   information from the internet and be connected anywhere, any time, any place.
   Specialized portals steer users of Web-enabled wireless devices to the information
   they are most likely to need


11. Compare the WAP and I-mode wireless Web standards.
   Answer : Wireless Application Protocol (WAP) is a system of protocols and
   technologies that lets cell phones and other wireless devices with tiny displays,
   low bandwidth cionnections, and minimal memory access Web-based information
   and services.I-mode is a rival standard developed by Japan’s NTT DoCoMo
   mobile phone network. It is widely used in Japan and is being introduced to
   Europe. I-mode uses compact HTML to deliver content, making it easier for
   business to converr their HTML web sites to mobile service.


12. Describe the organizational benefits of internet and web technology.
   Answer : The internet, intranets, and extranets are becoming the principal
   platforms for electronic commerce, electronic business, and the digital firm
   because this technology provides so many benefits. The internet’s global
   connectivity; ease of use, low cost, and multimedia capabilities can be used to
   create interactive applications, and provide services and products. By using
   internet technology, organizations can reduce communication and transaction
   cost, anhance coordination and collaboration, and accelerate the distribution of
   knowledge. Internet benefits to organizations
          Connectivity and global reach
          Reduced communication costs
          Lower transaction costs
          Reduced agency costs
          Interactivity, flexibiliry, and customization
          Accelerated distribution of knowledge


13. list and describe the principal technologies for supporting electronic commerce
   Answer : Business seriously pursuing electronic commerce and alectronic
   business need special tools for maintaining their web sites. These tools include
   Web server and electronic commerce server software,customer tracking and
   personalization tools, Web content management tools, and Web site performance
   monitoring tools. Web servers as the software necessary to run Web sites,
   intranets, and extranets. The core capabilities of web server software revolve
   around locating and managing stored Web pages.Customer tracking and
   personalizarion toolos have several main goals :
          Collecting and storing data on the behaviour of on-line customers and
           combining that data with data already stored in the company’s back-office
           system
          Analyzing the data in order better to understand the behaviour of on-line
           customers
          Identifyng developing customer trends


14. Under what conditions should firms consider Web hosting services?
   Answer : Companies that lack the financial or technical resources to operate their
   own web sites or electronic commerce service can use Web hosting services. A
   web hosting service maintains a large web server computer or a series of servers
   and provides fee-paying subscribes with space to maintain their Web sites. The
   subscribing companies may create their own web pages or have the hosting
   service or a web design firm create them


15. Describe five problems posed by the new information technology (IT)
   infrastructure.
   Answer : The challenge of managing the new information technology
   infrastructure
          Loss of managing
           Managing information system technology and corporate data are proving
           much more difficult in a distributed environment because of the lack of a
           single, central point where needed management can occur.
          Connectivity and application Integration
           We have already described the connectivity problems created by
           incompatible networks and standards, including connectivity problems for
           wireless networks
          Organizational change requirements
           Enterprise-wide computing provides an opportunity to reengineer the
           organization into a more effective unit, but it will only create problems or
           chaos if the underlying organizational issues are not fully addressed
           (duchessi and Chengalur-Smith, 1998)


          Hidden costs of Enterprise Computing
           Many companies have found that the savings they expected from
           distributed clients/ server computing did not materialize because of
           unexpected costs.
          Scability, Relyability, and security
           Companies seeking to digitally enable their business require robust IT
           infractructures providing plentiful bandwidth and storage capacity for
           transmitting and maintaining all of the data generated by electronic
           business transactions


16. Describe some solutions to the problems posed by the new IT infrastrucute.
   Answer : Organizations can meet the challenges posed by the new IT
   infrastructure by planning for managing the business and organizational changes;
   increasing end- user training; asserting data administration disciplines; and
   considering connectivity, application integration, bandwidth, and cost controls in
   their technology planning

								
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