A TCP socket does not include____.
A. Source MAC address
B. Source port number
C. Destination IP address
Destination port number
查看答案
Which of following about UDP is not correct.
A. It is a reliable data transfer protocol
B. It is connectionless
C. no handshaking between UDP sender, receiver
D. it is a best effort service protocol
DNS uses ____ service.
A. TCP
B. UDP
C. Both TCP and UDP
D. None of above
The UDP header has only ____ fields.
A. 2
B. 4
C. 1
D. 3
Which of the following does not included in UDP header.
A. Source port number
B. Destination port number
Checksum
D. Sequence number
微信支付 
支付宝支付