Your device might be streaming movies, receiving mail, and downloading files simultaneously even though it is connected with one single wire. For different types of data, a mechanism is expected to process similar types of data at a single address, that address is referred to as a "port number". These numbers help identify different types of data and send the data to the correct address.
To view a web page, the device needs to send a request to the server to get access to this page. The server receives the request through a specific port, i.e., 80 for HTTP and 443 for HTTPS. Each protocol has its own port number, and these numbers help route the traffic to the correct application or service.
Port numbers are 16 bit values which start from 0 to 65535. There are three ranges of port numbers:
Well known ports (0 - 1023)
Registered port (1024 - 49151)
Dynamic ports (49152 - 65535)
Here are the following common port numbers:
Port No | Port | Description |
21 | FTP (File Transfer Protocol) | This port is used for transferring files between computers using the FTP protocol. |
22 | SSH (Secure Shell) | This port is used for secure remote login and other secure network services over an insecure network. |
23 | Telnet | This port is used for remote login to a computer using the Telnet protocol. This port is not used as it is insecure. |
25 | SMTP (Simple Mail Transfer Protocol) | This port is used for sending and receiving email using the SMTP protocol. |
53 | DNS (Domain Name System) | This port is used for resolving domain names to IP addresses using the DNS protocol. |
80 | HTTP (HyperText Transfer Protocol) | This port is used for transmitting and receiving data over the web using the HTTP protocol. |
443 | HTTPS (HTTP over SSl/TLS) | This port is used for transmitting and receiving secure data over the web using the HTTPS protocol. |
3306 | MySQL | This port is default port for the MySQL database management system |
3389 | RDP (Remote Desktop Protocol) | This port is used for connecting to a remote computer. |
8080 | Alternative HTTP connections | This port is often used for hosting web content on a HTTP port, or for running proxy servers. |