50 Common Ports You Should Know - GeeksforGeeks (2024)

FAQs

50 Common Ports You Should Know - GeeksforGeeks? ›

The TCP and UDP protocols have, separately, a port number which allows different program to connect to remote computers or one program to connect to different computers. This is a 16-bit number, which means that it can have 65536 different values. That limits the number of simultaneous connections you can have open.

The TCP and UDP protocols have, separately, a port number which allows different program to connect to remote computers or one program to connect to different computers. This is a 16-bit number, which means that it can have 65536 different values. That limits the number of simultaneous connections you can have open.

Ports 0 through 1023 are defined as well-known ports. Registered ports are from 1024 to 49151. The remainder of the ports from 49152 to 65535 can be used dynamically by applications.

HTTP Port-80 is used for HTTP (Hyper Text Transfer Protocol) connection by default. It is a popular and widely used port across the globe. Port 80 was introduced by Tim Berners-Lee in 1991 in the HTTP 0.9 document. The document states that if there is no port assigned for HTTP connection, Port 80 is used by default.

The host computer uses these ports to direct traffic to the associated process or service. Software-based ports are identified by 16-bit integers that range from 0 to 65535. The ports can be either static or dynamic. A static port is one whose association with a process or service does not change.

Port 3000 became a default choice for development servers due to its non-privileged status and low likelihood of conflict with other well-known ports. It's easy to remember and has become a standard in the dev community.

Originally, the Simple Mail Transfer Protocol (SMTP) used port 25. Today, SMTP should instead use port 587 — this is the port for encrypted email transmissions using SMTP Secure (SMTPS). Port 465 is also used sometimes for SMTPS. However, this is an outdated implementation and port 587 should be used if possible.

Is port 465 deprecated? ›

It is commonly used for the submission of outgoing mail. Port 465: This port was previously used for Secure SMTP (SMTPS). It has now been deprecated by the Internet Engineering Task Force (IETF), and its use is not recommended.

As you can see, SMTP config is simply: plain sents through port 25 and empty user and pass without TLS or SSL encryption. The security is based on IP whitelist.

FTP is a TCP based service exclusively. There is no UDP component to FTP. FTP is an unusual service in that it utilizes two ports, a 'data' port and a 'command' port (also known as the control port). Traditionally these are port 21 for the command port and port 20 for the data port.

A DNS server uses well-known port 53 for all its UDP activities and as its server port for TCP. It uses a random port above 1023 for TCP requests. A DNS client uses a random port above 1023 for both UDP and TCP.

For TCP and UDP, a port number is a 16-bit unsigned integer, thus ranging from 0 to 65535. For TCP, port number 0 is reserved and cannot be used, while for UDP, the source port is optional and a value of zero means no port.

Ruby Port is the most common type of port, known for its deep red color and bright, fruity flavors. It's typically aged for a shorter period (about three years), resulting in a fresh, vibrant taste with less complexity.

USB Type-A

This is the most common port found on all laptops and desktops. The near universal use of USB Type-A means you can easily connect a wide range of peripherals and devices straight to your computer, such as keyboards, mice, printers, microphones, external storage devices, and more.

Over the years, several serial port interface standards for connecting computers to peripheral devices have been developed. These standards include RS-232, RS-422, and RS-485 — all of which are supported by the serialport object. The most widely used standard is RS-232.