normal是什么意思传输层小测题

2021年1月27日发(作者：药丸)
Quizzes for Transport Layer
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Department of Computer Science
One of the main duties of the transport layer is to provide ____________ communication.

A)

node-to-node

B)

host-to-host

C)

process-to-process

D)

None of the choices are correct


A client program normally uses ____________ port number. A server program normally uses
__________ port number.

A)

a well-known; an ephemeral

B)

an ephemeral; a well-known

C)

a private; a well- known

D)

None of the choices are correct
A socket address is a combination of __________.
A)

A MAC address and a logical address
B)

A MAC address and a port number
C)

a user-specific address and a logical address
D)

None of the choices are correct
______________
means
accepting
items
from
more
than
one
source.
______________
means delivering items to more than one source.

A)

Demultiplexing; Multiplexing

B)

Multiplexing; Demultiplexing

C)

Encapsulation; Decapsulation

D)

Pulling; Pushing
________ means the producer delivers the items when they are produced. _______ means the
consumer takes the items when it is ready to do so.

A)

Pushing; pulling

B)

Pulling; pushing

C)

Forwarding; accepting

D)

None of the choices are correct
In the stop-and-wait protocol, the maximum send window size is ______ and the maximum
receive window size is _______ where m is the number of bits in the sequence.

A)

1; 1

B)

2
m
;
–
1

C)

1; 2
m


D)

2
m
; 2
m

In
the
Go-Back-N
protocol,
the
maximum
send
window
size
is
______
and
the
maximum
receive window size is _______, where m is related to the number of bits in the sequence
number.

A)

1; 1

B)

1; 2
m


C)

2
m
–
1
; 1
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D)

2
m
–
1
; 2
m
–
1

8.

In the selective-repeat protocol, the maximum send window size is ______ and the maximum
receive window size is _______, where m is the number of bits in the sequence.

A)

1; 1

B)

1; 2
m
–
1


C)

2
m
–
1
; 1

D)

2
m
–
1
; 2
m
–
1

9.

UDP is a ________________ transport protocol.

A)

connectionless, reliable

B)

connection-oriented, unreliable

C)

connectionless, unreliable

D)

None of the choices are correct
10.

UDP is an acronym for _______.

A)

User Delivery Protocol

B)

User Datagram Procedure

C)

User Datagram Protocol

D)

None of the choices are correct
11.

At the transport layer, to define the processes, we need two identifiers called ____________.



A)

logical addresses



B)

physical addresses



C)

port addresses



D)

None of the choices are correct
12.

The ports ranging from 0 to 1,023 are called the ___________ ports. The ports ranging from
1,024 to 49,151 are called ___________ ports. The ports ranging from 49,152 to 65,535 are
called the ___________ ports.



A) well-known; registered; dynamic or private



B) registered; dynamic or private; well-known



C) private or dynamic; well-known; registered



D) private or dynamic; registered; well-known
13.

UDP and TCP are two protocols at the ___________ layer.



A) data link



B) network



C) transport



D) application
14.

Which of the following functions are performed by UDP?



A) process-to-process communication



B) host-to-host communication



C) node-to-node communication



D) None of the choices are correct
15.

A port number is _______ bits long.

A)
8

B)
16

C)
32

D)
64
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Which of the following does UDP provide?
A)
flow control
B)
connection-oriented delivery
C)
error control
D)
None of the choices are correct
The source port number on the UDP user datagram header defines _______.
A)
the sending computer
B)
the receiving computer
C)
the process running on the sending computer
D)
None of the choices are correct
To use the services of UDP, we need ________ socket addresses.
A)
four
B)
two
C)
three
D)
None of the choices are correct
UDP packets are called __________ .
A)
user datagrams
B)
segments
C)
frames
D)
None of the choices are correct
UDP packets have a fixed-size header of _______ bytes.
A)
16
B)
8
C)
40
D)
32
TCP is a __________ protocol.
A)
byte-oriented
B)
message-oriented
C)
block- oriented
D)
None of the choices are correct
TCP groups a number of bytes together into a packet called a ___________.
A)
user datagram
B)
segment
C)
datagram
D)
None of the choices are correct
TCP is a(n) ___________ protocol.
A)
connection-oriented
B)
connectionless
C)
both connection- oriented and connectionless
D)
None of the choices are correct
TCP is a(n) _______ transport protocol.
A)
unreliable
B)
best-effort delivery
C)
reliable

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D)
None of the choices are correct
TCP uses _________________ to check the safe and sound arrival of data.
A)
an acknowledgment mechanism
B)
out-of-band signaling
C)
the services of another protocol
D)
None of the choices are correct
The bytes of data being transferred in each connection are numbered by TCP. The numbering
starts with a __________________.
A)
0
B)
1
C)
randomly generated number
D)
None of the choices are correct
In TCP, the sequence number for each segment is the number of the _______ byte (virtual
byte) carried in that segment.
A)
first
B)
last
C)
middle
D)
None of the choices are correct
Communication in TCP is ___________.
A)
simplex
B)
half- duplex
C)
full-duplex
D)
None of the choices are correct
In
TCP,
the
value
of
the
acknowledgment
field
in
a
sent
segment
defines
the
sequence
number related to the ______ byte a party expects to receive next.
A)
first
B)
last
C)
next
D)
None of the choices are correct
The inclusion of the checksum in the TCP segment is ________.
A)
optional
B)
mandatory
C)
depends on the type of data
D)
None of the choices are correct
In TCP, a SYN segment consumes _____ sequence number(s).
A)
no
B)
one
C)
two
D)
None of the choices are correct
In TCP, a SYN + ACK segment consumes _____ sequence numbers.
A)
no
B)
three
C)
two
D)
one
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In TCP, an ACK segment, if carrying no data, consumes ______ sequence number(s).
A)
no
B)
one
C)
two
D)
None of the choices are correct
The connection establishment procedure in TCP is susceptible to a serious security problem
called the _________ attack.
A)
ACK flooding
B)
FIN flooding
C)
SYN flooding
D)
None of the choices are correct
The SYN flooding attack belongs to a group of security attacks known as a _____ attack.
A)
denial of service
B)
replay
C)
man-in-the middle
D)
None of the choices are correct
In TCP, a FIN segment consumes ____ sequence numbers if it does not carry data.
A)
two
B)
three
C)
no
D)
one
In TCP, a FIN + ACK segment consumes _____ sequence number(s) if it does not carry data.
A)
two
B)
three
C)
one
D)
no
In
TCP,
one
end
can
stop
sending
data
while
still
receiving
data.
This
is
called
a
______
termination.
A)
half- close
B)
half-open
C)
full-close
D)
None of the choices are correct
TCP sliding windows are __________ oriented.
A)
packet
B)
segment
C)
byte
D)
None of the choices are correct
In TCP, the size of the send window is the ________ of rwnd and cwnd.
A)
maximum
B)
sum of
C)
minimum
D)
None of the choices are correct
In TCP, the window should not be _________.
A)
opened