A socket is the interface between ( )within a host.
A. the network layer and the link layer
B. the link layer and the physical layer
C. the application layer and the transport layer
D. the transport layer and the network layer
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In the following applications, which one is a loss-tolerant application?( )
A. E-mail
B. file transfer
C. instant messaging
D. real-time audio
In the following applications, which one is a bandwidth-sensitive application?( )
A. E-mail
B. web application
C. real-time audio
D. file transfer
The service of TCP can't guarantee ( ).
A. delivery of all data without error
B. delivery of all data in the proper order
C. the rate of delivery
D. congestion control
In the following applications, which one uses UDP?( )
A. E-mail
B. web application
C. file transfer
DNS
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