Question

Which of the following ports is wrongly matched?
80::HTTP
443::SMTPS
23::Telnet
25::SMTP

Answer 1

First of all what is port number so,

A port number is a way to identify specific process to which internet or other other network message is to be forwarded when it is arrived at server

Now,

If you observe the transport layer carefully there are two defined protocols,

TCP

(Transmission control protocol)

And

UDP

(User datagram protocol)

UDP is connectionless protocol (Less reliable but faster)

So,

Port numbers are appended to IP header in the UDP protocol

Now,

Port numbers are well defined and fixed for every service

Their is no logical explanation to any port number , it needs to be remembered by the user

So,

If you look at the options all the ports are matched correctly except

Port 443

Which is for

(https)

Https and http are different,

https are the more secured protocols

So,

Port 443 is matched incorrectly