Every computer system has __________ TCP and ______________ UDP ports. The first _________ are said to be well-known ports.
A.
65,534, 65,534, 1024
B.
65,535, 65,535, 1023
C.
65,535, 65,534, 1023
D.
65,535, 65,533, 1024
Explanation:
Every computer system has 65,535 TCP and 65,535 UDP ports. The first
1023 are well-known ports, which mean that a specific port number under 1024 is
usually mapped to a well-known and used protocol. For instance, port 80 is almost
always mapped to the Hypertext Transfer Protocol (HTTP), port 21 is mapped to the
File Transfer Protocol (FTP), and port 25 is mapped to SMTP. These ports can be
reconfigured so port 21 is mapped to HTTP, let’s say, but that is very uncommon.