TCP UDP Port Numbers - Quiz Explanation
The answers you selected are indicated below, along with text that explains the correct answers.
1.
You have just installed a DNS server and a Web server on your UNIX system. Which two transport-layer protocols do these two daemons use?
Please select the best answer.
A.
IP and UDP
B.
UDP and TCP
C.
TCP and IP
D.
HTTP and UDP
The correct answer is B.
A DNS server and a Web server would use, respectively, UDP and TCP. UDP allows for simple rely-request transactions, and TCP supports ongoing reliable data transfer.
2.
What information is presented in the file /etc/services?
Please select the best answer.
A.
A list of conventional names for TCP/IP services and associated well-known port numbers
B.
A list of client/server transactions using TCP/IP services
C.
A list of network services available and the protocols they are using on a UNIX system
D.
A list of client processes on one machine and their corresponding server processes on another
The correct answer is A.
The information presented in the file /etc/services is a list of conventional names for TCP/IP services and associated well-known port numbers.
3.
A process opening a connection on a port numbered from 1 to 1023 requires:
Please select the best answer.
A.
A telnet connection
B.
Root permissions
C.
A system administrator's password
D.
Read and write permission
The correct answer is B.
A process opening a connection on a port numbered from 1 to 1023 requires root permissions. Processes using these ports must have special permissions, such as root, on the originating machine.
