Computer Ports Definition
Expert – Computing
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The Computer ports definition means the port is the logical endpoint of a network connection that is used to exchange information. These ports are assigned a unique number to help identify them separately.
When data is exchanged through the Internet between a web client and a web server, a mutual connection is established between them. To form this mutual connection, both the web client and the web server need to adhere to the same set of rules. This process is called a protocol.
In fact, a set of standard protocols is created for different services such as transmitting web content, exchange files, providing secure web access, domain name services, etc. Different port numbers are assigned to these protocols to send and receive these services between client computers and the servers.
What are the most commonly used ports?
The computer port definition is easily understood with examples. Some of the standard ports used in computer networking are described below:
- Port 80 is used by hypertext transfer protocol (HTTP) to transmit web content from a web server to a web client over the Internet. This port is used by your computer when you load web content such as a web page using your browser.
- Port 21 is used by file transfer protocol (FTP) to transfer files between a client computer and the server. This port is used by your computer when you upload or download files using an FTP client application. For example FileZilla.
- Port 443 is used by hypertext transfer protocol secure (HTTPS), an extension of HTTP which runs on SSL (Secure Sockets Layer) of the computer network. This port is used by your computer when you log into a secure web page using your credentials such as your username and password.
- Port 25 is used by the simple mail transfer protocol (SMTP) to route emails. This port is used by your computer when you send emails from an application. For example Microsoft Outlook. Gmail.
- Port 53 is used by the domain name system (DNS) services. This port is used by your computer to convert the textual domain names that you typed into your browser into numerical IP addresses that computers require to communicate with each other.