计网多选

BrotherCall · 2025-02-26 13:40:22 · 个人记录

1. (多选题) The routing table contains the following key information:

• 翻译: 路由表包含以下关键信息：
• 选项:
  • A. Source Network
  • B. Destination Network
  • C. Mask
  • D. Interface
• 正确答案: B: Destination Network, C: Mask, D: Interface

2. (多选题) Which of the fields below are in a UDP segment header?

• 翻译: 以下哪些字段在 UDP 段头中？
• 选项:
  • A. Checksum
  • B. Payload
  • C. Source port number
  • D. Length
• 正确答案: ACD: Checksum; Source port number; Length

3. (多选题) The network layer is implemented in ( )

• 翻译: 网络层在以下哪些设备中实现？
• 选项:
  • A. wired Internet-connected devices but not wireless Internet-connected devices.
  • B. Hosts at the network's edge.
  • C. Switches in a local area network.
  • D. Routers in the network core.
• 正确答案: BD: Hosts at the network's edge.; Routers in the network core.

4. (多选题) With the development of the Internet, various problems of the IPv4 protocol began to appear:

• 翻译: 随着互联网的发展，IPv4 协议的各种问题开始显现：
• 选项:
  • A. Difficulty in security management
  • B. Insufficient public IP addresses
  • C. Low efficiency of private address communication
  • D. No optional field in the header
• 正确答案: ABC: Difficulty in security management; Insufficient public IP addresses; Low efficiency of private address communication

5. (多选题) #Generally, a newly-bought laptop (that has just been unsealed) needs to get ( ) to get access to the Internet.

• 翻译: #通常，一台新购买的笔记本电脑（刚拆封）需要获取 ( ) 才能访问互联网。
• 选项:
  • A. an IP address
  • B. an MAC address
  • C. address of the first hop router
  • D. address of the DNS server
• 正确答案: ACD: an IP address; address of the first hop router; address of the DNS server

6. (多选题) Two generic forms of pipelined protocols for packets are:

• 翻译: 数据包的两种通用流水线协议形式是：
• 选项:
  • A. GBM
  • B. SR
  • C. AS
  • D. GBN
• 正确答案: BD: SR; GBN

7. (多选题) The types of links according to the multiple access protocol in LAN include:

• 翻译: 根据局域网中的多路访问协议，链路类型包括：
• 选项:
  • A. bus
  • B. star
  • C. Point-to-point
  • D. Broadcast
• 正确答案: CD: Point-to-point; Broadcast

8. (多选题) Which one(s) about IP header is(are) Right?

• 翻译: 关于 IP 头部的哪一项（或哪些）是正确的？
• 选项:
  • A. MF: The value 0 indicates "Last Fragment"
  • B. Source Address: it has 16 bits to mark the source IP address
  • C. Fragment Offset: it has 13 bits to position a fragment in the original packet
  • D. DF. The value 0 indicates "Don't Fragment"
• 正确答案: AC: MF: The value 0 indicates "Last Fragment"; Fragment Offset: it has 13 bits to position a fragment in the original packet

9. (多选题) Channel partitioning technology can divide the channel into smaller pieces like ( ).

• 翻译: 信道划分技术可以将信道划分为更小的部分，例如 ( )。
• 选项:
  • A. MAC address
  • B. code
  • C. frequency
  • D. timeslot
• 正确答案: BCD: code; frequency; timeslot

10. (多选题) Common IGPs include:

• 翻译: 常见的内部网关协议（IGP）包括：
• 选项:
  • A. OSPF
  • B. IS-IS
  • C. BGP
  • D. RIP
• 正确答案: ABD: OSPF; IS-IS; RIP

11. (多选题) What transport services are provided to the application by UDP?

• 翻译: UDP 向应用程序提供哪些传输服务？
• 选项:
  • A. Best effort service.
  • B. Multiplexing & Demultiplexing.
  • C. Loss-free data transfer.
  • D. Flow Control.
• 正确答案: AB: Best effort service.; Multiplexing & Demultiplexing.

12. (多选题) Protocols define:

• 翻译: 协议定义了：
• 选项:
  • A. order of messages sent and received among network entities
  • B. transmission rate and lowest bit error rate in practice
  • C. actions taken on message transmission
  • D. format of messages sent and received among network entities
• 正确答案: ACD: order of messages sent and received among network entities; actions taken on message transmission; format of messages sent and received among network entities

13. (多选题) What is(are) mentioned in the classroom?

• 翻译: 课堂上提到了哪些内容？
• 选项:
  • A. ISP hopes to fully utilize the infrastructure that has already been built.
  • B. The network facilities belong to the national key infrastructure.
  • C. Developing countries have a "latecomer advantage" in building their network.
  • D. Many Chinese ISPs have gone global and developed businesses in the United States.
• 正确答案: ABC: ISP hopes to fully utilize the infrastructure that has already been built.; The network facilities belong to the national key infrastructure.; Developing countries have a "latecomer advantage" in building their network.

14. (多选题) Which of the following brands are related to Transport Layer?

• 翻译: 以下哪些品牌与传输层相关？
• 选项:
  • A. Android
  • B. MS Office
  • C. Wechat
  • D. MS Windows
• 正确答案: AD: Android; MS Windows

15. (多选题) The media used to transmit information on Ethernet networks include

• 翻译: 以太网中用于传输信息的介质包括：
• 选项:
  • A. coaxial cables
  • B. twisted pair cables
  • C. radio
  • D. optical fibers
• 正确答案: ABD: coaxial cables; twisted pair cables; optical fibers

16. (多选题) Currently, most mainstream wireless WAN solutions use mobile telecommunications cellular technologies such as ( ).

• 翻译: 目前，大多数主流的无线广域网解决方案使用移动通信蜂窝技术，例如 ( )。
• 选项:
  • A. 4G
  • B. 5G
  • C. 2G
  • D. LTE
• 正确答案: ABD: 4G; 5G; LTE

17. (多选题) The Network Layer in TCP/IP stack is formed with ( )

• 翻译: TCP/IP 协议栈中的网络层由 ( ) 组成。
• 选项:
  • A. Control Plane
  • B. Payload Plane
  • C. Header Plane
  • D. Data Plane
• 正确答案: AD: Control Plane; Data Plane

18. (多选题) Which one(s) is right about the IPv4 address?

• 翻译: 关于 IPv4 地址，以下哪项（或哪些）是正确的？
• 选项:
  • A. One IP address for each interface
  • B. A 32-byte identifier
  • C. Used in both hosts and routers
  • D. A four-byte identifier
• 正确答案: ACD: One IP address for each interface; Used in both hosts and routers; A four-byte identifier

19. (多选题) Which of the following addresses can not be used by an interface in the 223.1.3/29 subnet network?

• 翻译: 以下哪些地址不能在 223.1.3/29 子网网络中的接口上使用？
• 选项:
  • A. 223.1.3.2
  • B. 223.1.3.16
  • C. 223.1.3.28
  • D. 223.1.2.6
• 正确答案: BCD: 223.1.3.16; 223.1.3.28; 223.1.2.6

20. (多选题) Assume that the data is 10110011 and the code generator is 11001, then what is/are Right?

• 翻译: 假设数据为 10110011，生成多项式为 11001，那么以下哪项（或哪些）是正确的？
• 选项:
  • A. the generator can be expressed as G(x)=x^5+x^4+x
  • B. the generator can be expressed as G(x)=x^4+x^3+1
  • C. the sent data is 101100111001
  • D. the sent data is 101100110100
• 正确答案: BD: the generator can be expressed as G(x)=x^4+x^3+1; the sent data is 101100110100

21. (多选题) Which one(s) about Packet Fragmentation and Reassembly is(are) Right?

• 翻译: 关于分组分片和重组，以下哪项（或哪些）是正确的？
• 选项:
  • A. When fragments are transmitted, the last router will reassemble them into the original packet.
  • B. The size of each fragment cannot exceed the MTU.
  • C. Each fragment shares the same IP header information except for the Fragment Offset and Flags fields.
  • D. Each fragment is an independent IP packet.
• 正确答案: BCD: The size of each fragment cannot exceed the MTU.; Each fragment shares the same IP header information except for the Fragment Offset and Flags fields.; Each fragment is an independent IP packet.

22. (多选题) As we mentioned in the classroom, which one(s) below can be called "protocol"?

• 翻译: 正如我们在课堂上提到的，以下哪项（或哪些）可以称为“协议”？
• 选项:
  • A. Phone call manners
  • B. Traffic rules
  • C. Sea waves
  • D. TCP connection
• 正确答案: ABD: Phone call manners; Traffic rules; TCP connection

23. (多选题) What are the principal components of the IPv4 protocol?

• 翻译: IPv4协议的主要组成部分有哪些？
• 选项:
  • A. Routing algorithms and protocols like OSPF and BGP
  • B. IPv4 datagram format
  • C. IPv4 addressing conventions
  • D. Packet handling conventions at routers
• 正确答案: BCD: IPv4 datagram format; IPv4 addressing conventions; Packet handling conventions at routers

24. (多选题) Which one(s) about circuit switching is(are) Right?

• 翻译: 关于电路交换，以下哪项（或哪些）是正确的？
• 选项:
  • A. Circuit switching establishes a dedicated path for the duration of the connection.
  • B. Resources are allocated dynamically in circuit switching.
  • C. Circuit switching is suitable for long, continuous data transfers.
  • D. Circuit switching does not require a setup phase before data transmission.
• 正确答案: AC: Circuit switching establishes a dedicated path for the duration of the connection.; Circuit switching is suitable for long, continuous data transfers.

25. (多选题) Which one(s) of the domain names below belongs to an institute in China?

• 翻译: 以下哪个（些）域名属于中国的机构？
• 选项:
  • A. www.bhu.edu.cn
  • B. www.bu.edu
  • C. sstc.neuq.edu.cn
  • D. www.whitehouse.gov
• 正确答案: AC: www.bhu.edu.cn; sstc.neuq.edu.cn

26. (多选题) Which one(s) about packet switching is(are) Right?

• 翻译: 关于分组交换，以下哪项（或哪些）是正确的？
• 选项:
  • A. simpler, no call setup
  • B. no resource sharing
  • C. protocols needed for reliable data transfer
  • D. great for bursty data
• 正确答案: ACD: simpler, no call setup; protocols needed for reliable data transfer; great for bursty data

27. (多选题) The Internet is a super-large network consisting ( ) networks around the world.

• 翻译: 互联网是一个由全球范围内的( )网络组成的超大型网络。
• 选项:
  • A. government
  • B. public
  • C. commercial
  • D. academic
• 正确答案: ABCD: government; public; commercial; academic

28. (多选题) Which applications are sensitive to packet loss?

• 翻译: 哪些应用对数据包丢失比较敏感？
• 选项:
  • A. Zoom Online Lecture
  • B. Email
  • C. Web
  • D. Live Streaming
• 正确答案: BC

29. (多选题) Which organization(s) has played a significant role in the development of the Internet?

• 翻译: 哪些组织在互联网的发展中发挥了重要作用？
• 选项:
  • A. ARPA
  • B. IANA
  • C. IEEE
  • D. NSF
• 正确答案: ABCD: ARPA; IANA; IEEE; NSF

30. (多选题) Compared with wired networks, WLANs have the following benefits:

• 翻译: 与有线网络相比，无线局域网（WLAN）具有以下优势：
• 选项:
  • A. provide wireless network coverage in places with difficult cabling
  • B. provide guaranteed bandwidth to industry clients
  • C. ideal for scenarios where users are often moving, such as in office buildings
  • D. free from cable and port location constraints
• 正确答案: ACD: provide wireless network coverage in places with difficult cabling; ideal for scenarios where users are often moving, such as in office buildings; free from cable and port location constraints

31. (多选题) What is the concept of a “good” path for a routing protocol?

• 翻译: 对于路由协议来说，“好的”路径的概念是什么？
• 选项:
  • A. A path that has little or no congestion.
  • B. A path that has a minimum number of hops.
  • C. A low delay path.
  • D. A high bandwidth path.
• 正确答案: ABCD: A path that has little or no congestion.; A path that has a minimum number of hops.; A low delay path.; A high bandwidth path.

32. (多选题) *Which of these protocols are collision-free?

• 翻译: 以下哪些协议是无碰撞的？
• 选项:
  • A. FDMA
  • B. Token-passing
  • C. Aloha
  • D. TDMA
• 正确答案: ABD: FDMA; Token-passing; TDMA

33. (多选题) The codes in command line windows to execute 3 delay measurements between hosts on the Internet are ( ).

• 翻译: 在命令行窗口中用于执行互联网主机之间3次延迟测量的命令是( )。
• 选项:
  • A. reboot
  • B. calc
  • C. traceroute
  • D. tracert
• 正确答案: CD: traceroute; tracert

34. (多选题) What real-world examples are referred to during the NETFUN class delivery?

• 翻译: 在NETFUN课程中提到了哪些现实世界的例子？
• 选项:
  • A. The importance of becoming a standard-setting institute in the Internet Industry.
  • B. The value of symbols and figures, such as domain names.
  • C. The computer network has developed fully and perfectly.
  • D. Scarcity of the Internet resources, e.g. IP Address.
• 正确答案: ABD: The importance of becoming a standard-setting institute in the Internet Industry.; The value of symbols and figures, such as domain names.; Scarcity of the Internet resources, e.g. IP Address.

35. (多选题) Which protocols below handle the process-process data transfer?

• 翻译: 以下哪些协议处理进程到进程的数据传输？
• 选项:
  • A. PPPoE
  • B. UDP
  • C. TCP
  • D. SMTP
• 正确答案: BC: UDP; TCP

36. (多选题，5分)

The problem is to distribute a file of size F = 9 Gbits to each of these 6 peers. Suppose the server has an upload rate of u = 90 Mbps.
The 6 peers have upload rates of: u1 = 25 Mbps, u2 = 30 Mbps, u3 = 12 Mbps, u4 = 20 Mbps, u5 = 24 Mbps, and u6 = 22 Mbps
The 6 peers have download rates of: d1 = 12 Mbps, d2 = 25 Mbps, d3 = 40 Mbps, d4 = 25 Mbps, d5 = 10 Mbps, and d6 = 22 Mbps

What is(are) the best software to accomplish this task?

• 选项:
  • A. uTorrent
  • B. FTP
  • C. BitTorrent
  • D. Internet Explorer
• 正确答案: AC: uTorrent; BitTorrent

37. (多选题) According to the lecturing in the classroom, what inspiration(s) can we get from the "two-army problem" (aka two generals on two distant mountains must agree on a cooperate time) model?

• 翻译: 根据课堂讲解，“两军问题”（即两座山上的将军必须就合作时间达成一致）模型给我们带来了哪些启示？
• 选项:
  • A. Retransmitted messengers by both generals can solve the problem.
  • B. Messengers can fail by going through the channel between two mountains.
  • C. If the generals can send only messengers, then no solution will work.
  • D. The absence of a messenger can be detected by the generals.
• 正确答案: BC: Messengers can fail by going through the channel between two mountains.; If the generals can send only messengers, then no solution will work.

38. (多选题) In the simple TCP transmission, assume the client has a SendBase of 50, and the server has a SendBase of 90. Then which value is/are 90 below?

• 翻译: 在简单的TCP传输中，假设客户端的SendBase为50，服务器的SendBase为90。那么哪些值在90以下？
• 选项:
  • A. Seq-A
  • B. Ack-B
  • C. Ack-D
  • D. Seq-C
• 正确答案: BD

39. (多选题) According to the delivery, which one(s) below can we get a TLD domain name from?

• 翻译：根据课程内容，以下哪些平台可以获取顶级域名（TLD）？
• 选项：
  • A. Alibaba Cloud Service
  • B. NEUQ Cloud Service
  • C. Tencent Cloud Service
  • D. Huawei Cloud Service
• 正确答案：ACD: Alibaba Cloud Service; Tencent Cloud Service; Huawei Cloud Service

40. (多选题) What is meant by an IP subnet?

• 翻译：IP子网的含义是什么？
• 选项：
  • A. A set of devices that always have a common first 16 bits in their IP address.
  • B. A set of devices all manufactured by the same equipment maker/vendor.
  • C. A set of devices that have a common set of leading high-order bits in their IP address.
  • D. A set of device interfaces that can physically reach each other without passing through an intervening router.
• 正确答案: CD: A set of devices that have a common set of leading high-order bits in their IP address.; A set of device interfaces that can physically reach each other without passing through an intervening router.

41. (多选题) Which one(s) about MAC address is correct?

• 翻译：关于MAC地址，以下哪些说法是正确的？
• 选项：
  • A. NIC manufacturer buys portion of MAC address space
  • B. MAC address allocation is administered by ICANN
  • C. It is a six-byte address
  • D. Generally in hexadecimal (base 16) notation
• 正确答案: ACD: NIC manufacturer buys portion of MAC address space; It is a six-byte address; Generally in hexadecimal (base 16) notation

42. (多选题) Which one(s) about Routing Table is(are) Right?

• 翻译：关于路由表，以下哪些说法是正确的？
• 选项：
  • A. When a router receives an IP packet, it checks the MAC address in the packet header and searches its routing table for an entry.
  • B. It is a data table stored on each router.
  • C. It is like a map, on which you can search for the path to a specific destination network address.
  • D. It has many entries, each indicating a route that corresponds to a destination network.
• 正确答案: BCD: It is a data table stored on each router.; It is like a map, on which you can search for the path to a specific destination network address.; It has many entries, each indicating a route that corresponds to a destination network.

43. (多选题) There are many error detection methods, such as ( ).

• 翻译：有许多错误检测方法，例如（ ）。
• 选项：
  • A. QoS check
  • B. CRC check
  • C. checksum check
  • D. parity check
• 正确答案: BCD: CRC check; checksum check; parity check

44. (多选题) Which one(s) about circuit switching is(are) Right?

• 翻译：关于电路交换，以下哪些说法是正确的？
• 选项：
  • A. dedicated resources
  • B. idle if not used by call
  • C. low cost in business
  • D. better performance
• 正确答案: ABD: dedicated resources; idle if not used by call; better performance

45. (多选题)Consider two hosts, A and B connected by a single link with data rate R and propagation delay of d_prop, Host A is to send a packet of size L to Host B. The packet transmission delay is d_trans. Suppose Host A begins to transmit the packet at time t=0. Which one(s) is(are) Right?

• 选项：
  • A. Suppose d_prop is less than d_trans. At time t=d_trans, the first bit of the packet is still in the link.
  • B. At time t=d_trans, the last bit of the packet is just leaving host A.
  • C. Suppose d_prop is greater than d_trans. At time t=d_trans, the first bit of the packet has reached host B.
  • D. Suppose d_prop is less than d_trans. At time t=d_trans, the first bit of the packet is already in host B.
• 正确答案:BD

46. (多选题) What is(are) the transmission rate(s) of Ethernet LANs?

• 翻译：以太网局域网的传输速率有哪些？
• 选项：
  • A. 10 Gbps
  • B. 10 Mbps
  • C. 1 Gbps
  • D. 100 Mbps
• 正确答案: ABCD: 10 Gbps; 10 Mbps; 1 Gbps; 100 Mbps

47. (多选题) What are access technologies below?

• 翻译：以下哪些是接入技术？
• 选项：
  • A. DSL over telephone line
  • B. Wifi (802.11)
  • C. 100 Mbps Ethernet
  • D. 4G
• 正确答案: ABCD: DSL over telephone line; Wifi (802.11); 100 Mbps Ethernet; 4G

48. (多选题) Consider an HTTP client that wants to retrieve a Web document at a given URL. The IP address of the HTTP server is initially unknown. What transport and application-layer protocols besides HTTP are needed in this scenario?

• 翻译：假设一个HTTP客户端想要检索一个给定URL的Web文档，而HTTP服务器的IP地址最初是未知的。在这种情况下，除了HTTP之外，还需要哪些传输层和应用层协议？
• 选项：
  • A. DNS
  • B. IP
  • C. TCP
  • D. UDP
• 正确答案: ACD: DNS; TCP; UDP

49. (多选题) Which of the following applications are(is) NOT delay sensitive

• 翻译：以下哪些应用对延迟不敏感？
• 选项：
  • A. voice teleconferencing
  • B. web
  • C. email
  • D. file transfer
• 正确答案: BCD: web; email; file transfer

50. (多选题) The 2-way handshake will not always work in network due to:

• 翻译：双向握手在网络中有时无法正常工作，原因包括：
• 选项：
  • A. variable delays
  • B. retransmitted messages (e.g. req_conn(x)) due to message loss
  • C. can’t “see” other side
  • D. message reordering
• 正确答案: ABCD: variable delays; retransmitted messages (e.g. req_conn(x)) due to message loss; can’t “see” other side; message reordering

51. (多选题) Why is there a UDP?

• 翻译：为什么存在UDP？
• 选项：
  • A. no connection establishment
  • B. no connection state at sender, receiver
  • C. no congestion control
  • D. small header size
• 正确答案: ABCD: no connection establishment; no connection state at sender, receiver; no congestion control; small header size

52. (多选题) An application may choose UDP for a transport protocol because:

• 翻译：应用程序可能选择UDP作为传输协议的原因是：
• 选项：
  • A. have more control of the physical materials
  • B. have more control on when the segment is sent
  • C. have more control of the edge network bandwidth
  • D. have more control of what data is sent in a segment
• 正确答案: BD: have more control on when the segment is sent; have more control of what data is sent in a segment

53. (多选题) What methods is adopted in TCP to create RDT service on top of IP's unreliable service?

• 选项：
  • A. cumulative acks
  • B. pipelined segments
  • C. port number
  • D. timeout
• 正确答案: ABD: cumulative acks; pipelined segments; timeout

54. (多选题) What is(are) the function(s) of ICANN?

• 选项：
  • A. allocates blocks of IP addresses
  • B. assigns domain names
  • C. manage MAC addresses
  • D. manages DNS
• 正确答案: ABD: allocates blocks of IP addresses; assigns domain names; manages DNS

55. (多选题) In TCP, retransmissions can be triggered by:

• 选项：
  • A. Internet Protocol
  • B. Physical layer protocols
  • C. timeout events
  • D. duplicate acks
• 正确答案: CD: timeout events; duplicate acks

56. (多选题) Which one(s) is(are) true of the TCP Reno?

• 选项：
  • A. initial rate is slow but ramps up exponentially fast
  • B. on loss event, ssthresh is set to 1/2 of cwnd
  • C. additively decrease window size until loss occurs
  • D. when cwnd≥ssthresh, add 1 MSS every RTT
• 正确答案: ABD: initial rate is slow but ramps up exponentially fast; on loss event, ssthresh is set to 1/2 of cwnd; when cwnd≥ssthresh, add 1 MSS every RTT

57. (多选题) How does a host get IP address?

• 选项：
  • A. through FTTH
  • B. through CSMA/CA
  • C. hard-coded
  • D. through DHCP
• 正确答案: CD: hard-coded; through DHCP