信息系统复习参考7(8)

71) The ________ is special software that routes and manages communications on the network and coordinates networks resources. Answer: network operating system/NOS Diff: 2 Page Ref: 248 AACSB: Use of IT CASE: Comprehension Objective: 7.1

72) A(n) ________ is a device that forwards packets of data through different networks, ensuring that the data gets to the right address. Answer: router Diff: 2 Page Ref: 248 AACSB: Use of IT CASE: Comprehension Objective: 7.1

73) ________ computing is a distributed computing model in which some of the processing power is

located within small, inexpensive client computers. Answer: Client/server Diff: 2 Page Ref: 250 AACSB: Use of IT CASE: Comprehension Objective: 7.3

74) A(n) ________ signal is a discrete, binary waveform that transmits data coded into two discrete states such as 1-bits and 0-bits. Answer: digital Diff: 2 Page Ref: 252 AACSB: Use of IT CASE: Comprehension Objective: 7.2

75) ________ is the manner in which the components of a network are connected. Answer: Topology Diff: 2 Page Ref: 254 AACSB: Use of IT CASE: Comprehension Objective: 7.2

76) ________ is the dominant LAN standard at the physical network level. Answer: Ethernet Diff: 2 Page Ref: 254 AACSB: Use of IT CASE: Comprehension Objective: 7.2

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77) A(n) ________ is a commercial organization with a permanent connection to the Internet that sells temporary connections to retail subscribers. Answer: Internet service provider Diff: 2 Page Ref: 257 AACSB: Use of IT CASE: Comprehension Objective: 7.3

78) The backbone networks of the Internet are typically owned by long-distance telephone companies called ________.

Answer: network service providers Diff: 2 Page Ref: 259 AACSB: Use of IT CASE: Comprehension Objective: 7.3

79) A(n) ________ is software for locating and managing stored Web pages. Answer: Web server Diff: 2 Page Ref: 269 AACSB: Use of IT CASE: Comprehension Objective: 7.3

80) A(n) ________ is a box consisting of a radio receiver/transmitter and antennas that links to a wired network, router, or hub. Answer: access point Diff: 2 Page Ref: 277 AACSB: Use of IT CASE: Comprehension Objective: 7.1

81) How does packet switching work?

Answer: Packet switching is a method of slicing digital messages into parcels called packets, sending the packets along different communication paths as they become available, and then reassembling the packets once they arrive at their destinations. Packet switching makes much more efficient use of the communications capacity of a network than did circuit-switching. In packet-switched networks, messages are first broken down into small fixed bundles of data called packets. The packets include information for directing the packet to the right address and for checking transmission errors along with the data. The packets are transmitted over various communications channels using routers, each packet traveling independently. Packets of data originating at one source will be routed through many different paths and networks before being reassembled into the original message when they reach their destinations. Diff: 2 Page Ref: 250 AACSB: Analytic Skills

CASE: Analysis in terms of summarize Objective: 7.1

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82) Identify the layers of the Department of Defense reference model for TCP/IP, and describe how this model works.

Answer: The application layer enables client application programs to access the other layers and defines the protocols that applications use to exchange data. One of these application protocols is the Hypertext Transfer Protocol (HTTP), which is used to transfer Web page files. The transport layer is responsible for providing the application layer with communication and packet services. This layer includes TCP and other protocols. The Internet layer is responsible for addressing, routing, and packaging data packets called IP datagrams. The Internet Protocol is one of the protocols used in this layer. At the bottom of the reference model, the network interface layer is responsible for placing packets on and receiving them from the network medium, which could be any networking technology. Data sent from one computer to the other passes downward through all four layers, starting with the sending computer’s application layer and passing through the network interface layer. After the data reach the recipient host computer, they travel up the layers and are reassembled into a format the receiving computer can use. If the receiving computer finds a damaged packet, it asks the sending computer to retransmit it. This process is reversed when the receiving computer responds. Diff: 3 Page Ref: 251-252 AACSB: Analytic Skills

CASE: Analysis in terms of summarize Objective: 7.3

83) Describe and explain the idea of \Why or why not?

Answer: Network neutrality describes the current equal access by users to Internet bandwidth, regardless of the services they are using on the Internet. Network neutrality is the idea that Internet service providers must allow customers equal access to content and applications, regardless of the source or nature of the content. Presently, the Internet is indeed neutral: all Internet traffic is treated equally on a first-come, first-serve basis by Internet backbone owners. The Internet is neutral because it was built on phone lines, which are subject to \laws require phone companies to treat all calls and customers equally. For example, someone using the Internet to download large movie files pays the same rate as someone accessing their e-mail. Now telecommunications and cable companies want to be able to charge differentiated prices based on the amount of bandwidth consumed by con …… 此处隐藏：4010字，全部文档内容请下载后查看。喜欢就下载吧 ……