计算机网络-第二次平时考试

计算机网络平时考试试题（带答案）

一、选择题

1．In the Ethernet frame structure, the Data field carries the ( ).

A.IP datagram

B.segment

C.frame

D.message

2．The units of data exchanged by a link-layer protocol are called ( ).

A. Frames

B. Segments

C. Datagrams

D. bit streams

3．The SYN segment is used for ( ).

A.TCP connection setup

B.TCP flow control

C.TCP congestion control

D.Closing a TCP connection

4．The ( ) is a worldwide computer network, that is, a network that interconnects millions of computing devices throughout the world.

A. Internet

B. Intranet

C. switch net

D. television net

5．The units of data exchanged by a link-layer protocol are called ( ).

A. Frames

B. Segments

C. Datagrams

D. bit streams

6．In Address：,（）indicates “host name”.

A. www

B. uzz

C. edu

D. cn

7. In the following options, which belongs to the network core? ( )

A. end systems

B. routers

C. clients

D. servers

8．The Internet’s connection-oriented service has a name, it is ( ).

A.TCP

B. UDP

C.TCP/IP

D.IP

9．There are two fundamental approaches to building a network core, ( ) and packet switching.

A. electrical current switching

B. circuit switching

C. data switching

D. message switching

10．A ( ) protocol is used to move a datagram over an individual link.

A. application-layer

B. transport-layer

C. network-layer

D. link-layer 11．Services provided by transport layer include ( ).

A.HTTP and FTP

B.TCP and IP

C.TCP and UDP

D.ICMP

12．IP addressing assigns an address to 223.10.198.250/29, the network address for this network is ( ).

A.223.10.198.248

B. 223.10.198.250

C. 223.10.198.0

D. 223.10.0.0

13．IP belongs to ( ).layer?

A.transport

work

C.data link

D. physical

14．Which of the following is correct? ( )

A. No two adapters have the same MAC address.

B. MAC broadcast address is FF-FF-FF-FF-FF-FF.

C. A portable computer with an Ethernet card always has the same MAC address, no matter where the computer goes. ( ).

D. All of the above

15．How many bits specify the IP protocol version in a datagram? ( ).

A.1 bit

B.2 bits

C.4 bits

D.8 bits

16．In the following applications, which one is a loss-tolerant application?

A E-mail

B file transfer

C instant messaging

D real-time audio 18．The Internet mail system has three components which they are ( ).

er agent, SMTP, POP3

B.SMTP, POP3, IMAP

er agent, SMTP, IMAP

er agent, SMTP, mail server