第一章单元测试

1、单选题：
‎    In a ________ network, a dedicated communications path is established between two stations through the nodes of the network.  The telephone network is the most common example.‌
选项：
A:    frame relay
B:    ATM
C:    circuit switching
D:    packet switching
答案: 【    circuit switching】

2、判断题：
‏It is not necessary for a device to interface with the transmission system in order to communicate.​‏​
选项：
A: 正确
B: 错误
答案: 【 错误】

3、判断题：
‍The basic building block of any communications facility is the transmission line.‎‍‎
选项：
A: 正确
B: 错误
答案: 【 正确】

4、判断题：
‏The LAN is owned by the same organization that owns the attached devices. ‍‏‍
选项：
A: 正确
B: 错误
答案: 【 正确】

5、填空题：
‏Networks that generally cover a large geographical area, require the crossing of public right-of-ways, consist of a number of interconnected switching nodes, and rely on circuits provided by a common carrier are ________.‏‏‏
答案: 【 Wide Area Networks (WANs)】

随堂测验：Internet前身

1、填空题：
‍The Internet evolved from the ________ which was developed in 1969 by the Advanced Research Projects Agency of the U.S. Department of Defense.‍
答案: 【 ARPANET】

随堂测验：网络相关知识提问

1、单选题：
‌   A network in which small chunks of data are passed through the network from node to node, and at each node the entire data chunk is received, stored briefly, and then transmitted to the next node, is a ________ network.‌
选项：
A:    packet switching
B:    ATM
C:    circuit switching
D:    frame relay
答案: 【    packet switching】

随堂测验：通信模型与通信任务相关知识提问

1、单选题：
​   The key elements of a simple communications model are ‏
选项：
A:    source, transmission, destination
B:     signal, transmission, receiver
C:    source, signal, destination
D:    source, signal, receiver
答案: 【    source, transmission, destination】

2、单选题：
‏   In situations in which an information exchange is interrupted due to a fault somewhere in the system, ________ techniques are needed to either resume activity at the point of interruption or to restore systems to their state prior to the beginning of the exchange.​
选项：
A:     flow control
B:    routing control
C: recovery
D:    error correction
答案: 【 recovery】

3、填空题：
‎__________ is required to assure that the source does not overwhelm the destination by sending data faster than they can be processed and absorbed.‎‎‎
答案: 【 Flow control】

三层模型

1、单选题：
‌The communication task can be organized into three relatively independent layers: network access layer, application layer, and ________ layer. ‏
选项：
A: transport
B: media
C: physical
D: processing
答案: 【 transport】

各层功能1

1、单选题：
The ________ layer contains the logic needed to support the various user applications. ‏‎‏
选项：
A:    internet
B:    physical
C:     transport
D: application
答案: 【 application】

2、判断题：
‍Procedures needed to allow data to traverse multiple interconnected networks is found in the internet layer of the TCP/IP protocol architecture. ‏‍‏
选项：
A: 正确
B: 错误
答案: 【 正确】

3、判断题：
‌The software used at the network access layer is not dependent on the type of network used because circuit switching, packet switching and local area networks all have the same standards. ‏‌‏
选项：
A: 正确
B: 错误
答案: 【 错误】

4、判断题：
‌In the application layer of TCP/IP, for each different type of application, a separate module is needed that is peculiar to that application. ‌‌‌
选项：
A: 正确
B: 错误
答案: 【 正确】

5、填空题：
‎In the TCP/IP protocol architecture, the ________ layer is concerned with specifying the characteristics of the transmission medium, the nature of the signals and the data rate.‎
答案: 【 physical】

层次模型

1、填空题：
‎The most widely used protocol architecture is the ________ protocol suite, which consists of physical, network access, internet, transport, and application layers. ‍
答案: 【 TCP/IP】

服务定义

1、填空题：
‏The services between adjacent layers in a protocol architecture are expressed in terms of ________ and parameters.‎
答案: 【 primitives】

第二章单元测验

1、单选题：
‌In a ________ the modules are arranged in a vertical stack.  Each layer in the stack performs a related subset of the functions required to communicate with another system.‎
选项：
A: protocol architecture
B: NSP
C: protocol data unit
D: frame relay
答案: 【 protocol architecture】

2、单选题：
‏The key features of a protocol are: syntax, semantics and ________.‏
选项：
A: presentation
B: timing
C: network access
D: peer layering
答案: 【 timing】

3、判断题：
​Each protocol provides a set of rules for the exchange of data between systems.‏
选项：
A: 正确
B: 错误
答案: 【 正确】

4、判断题：
​It is not necessary for each host on a subnet to have an unique global internet address.‎
选项：
A: 正确
B: 错误
答案: 【 错误】

5、填空题：
‌Each application on a computer has an address that is unique within that computer known as ________ or ports that allow the transport layer to support multiple applications at each computer​
答案: 【 Service Access Points (SAPs)】

运行

1、填空题：
​The addiction of control information to data is referred to as ________. ‍​‍
答案: 【 encapsulation】

2、填空题：
​The two commonly used transport level protocols used as part of the TCP/IP protocol suite are TCP and ________.‎
答案: 【 UDP】

传输损耗

1、单选题：
‍When signals at different frequencies share the same transmission medium the result may be ________ noise.‌
选项：
A: white
B: impulse
C: crosstalk
D: intermodulation
答案: 【 intermodulation】

2、判断题：
‍A major problem in designing a communications facility is transmission impairment.‎‍‎
选项：
A: 正确
B: 错误
答案: 【 正确】

3、填空题：
‏Thermal noise is also referred to as ________ noise.‎
答案: 【 white】

4、填空题：
‏Because of delay distortion some of the signal components of one bit position will spill over into other bit positions causing ________ interference, which is a major limitation to maximum bit rate over a transmission channel.‌
答案: 【 intersymbol】

相关概念

1、单选题：
‌A key parameter that characterizes any electromagnetic signal is ________, which is the width of the range of frequencies that comprises the signal.‏
选项：
A: wavelength
B: digital
C: analog
D: bandwidth
答案: 【 bandwidth】

2、单选题：
‏In ________ transmission signals are transmitted in only one direction; one station is the transmitter and the other is the receiver.‍
选项：
A: half duplex
B: simplex
C:  full duplex
D: multipoint
答案: 【 half duplex】

3、单选题：
​The term ________ is used to refer to the transmission path between two devices in which signals propagate directly from transmitter to receiver with no intermediate devices other than amplifiers or repeaters used to increase signal strength.​
选项：
A: direct link
B: unguided media
C: guided
D: wireless
答案: 【 direct link】

4、填空题：
‌Twisted pair, coaxial cable and optical fiber are examples of ________ media.‍
答案: 【 guided】

5、填空题：
​In a ________ guided configuration more than two devices share the same medium.‎​ ‎​‎
答案: 【 multipoint】

第三章单元测验

1、单选题：
‌A guided transmission medium is ________ if it provides a direct link between two devices and those are the only two devices sharing the medium.​
选项：
A: multipoint
B: simplex
C: point-to-point
D: wireless
答案: 【 point-to-point】

2、单选题：
‍A reduction in strength is ________.‌
选项：
A: delay distortion
B: attenuation
C: pulsing
D: interlacing
答案: 【 attenuation】

3、判断题：
‏In full-duplex