Which service does UDP not provide?
A. multiplexing
B. de-multiplexing
C. error-detection
D. error-correction
查看答案
There are three major events related to data transmission and retransmission in the TCP sender, which one is not in it?
A. data received from application above
B. de-multiplexing segment
C. timer timeout
D. ACK receipt
The Internet’s _____is responsible for moving packets from one host to another.
A. application layer
B. transport layer
C. network layer
D. link layer
In the following four descriptions, which one is correct?
A. If one host’s transport layer uses TCP, then its network layer must use virtual-circuit network.
B. Datagram network provides connection service
C. The transport-layer connection service is implemented in the router
D. The network-layer connection service is implemented in the router as well as in the end system.
There are 6 flag fields. Which one is to indicate that the receiver should pass the data to the upper layer immediately?
A. PSH
B. URG
C. ACK
D. RST
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