In order for devices to communicate with each other in a single network, whether an internal network (LAN) or on the Internet (WAN), we need three very important things:
IP address ( 192.168.1.1 ) ( 10.0.0.2 )
Port ( 80 - 25 - 110 - 21 - 53 - 23 )
Protocol ( HTTP - SMTP -pop - ftp - DNS - telnet or HTTPS
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IP address:
It is the digital identifier for any device (computer, mobile phone, printer) connected to an information network that operates on the Internet protocol package, whether it is an internal network or the Internet.
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Protocol:
It is a program that is automatically present in any operating system (Windows - Mac - Linux). Any operating system in the world has the HTTP protocol responsible for browsing the Internet.
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Port:
A software vulnerability in operating systems, and the number of these vulnerabilities ranges between 0 - 65536 software vulnerabilities, and each vulnerability works on a different protocol from the other.
Software vulnerability: an opening or gateway in all operating systems to regulate the entry and exit of data.
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Types of Protocols and Ports - We are now familiar with a number of the most famous Internet protocols:
SMTP or Simple Mail Transfer Protocol:
It is a protocol for sending e-mail over the Internet that works on Port 25.
POP or Post Office Protocol:
It is a protocol for receiving e-mail over the Internet and operates on Port 110.
FTP or Transfer Protocol File:
It is a protocol for downloading from the Internet and works on Port 21.
DNS or Domain Name System:
It is a protocol that translates domain names from words to numbers known as an IP address that works on Port 53.
Telnet or Terminal Network:
It is a protocol that allows users to run programs remotely and operates on Port 23.
