Network port definition
A network port is a communication endpoint on a computer or network device. It is a virtual connection point for sending or receiving data on a computer network. Network ports are designated with a number, and each port is associated with a specific network protocol. For example, port 80 is typically used for HTTP traffic, and port 443 is used for HTTPS traffic. Network ports are used to differentiate different types of network traffic and direct them to the appropriate application on a device.
How network ports work
When a device communicates with another device over a network, it sends and receives data through a specific port number. The device's IP address and port number together identify a unique connection point on the device. For example, a web server might listen for incoming HTTP traffic on port 80, while a separate application on the same device might listen for incoming traffic on port 8000.
Network port examples
Network ports are typically divided into three ranges: well-known ports (0-1023), registered ports (1024-49151), and dynamic/private ports (49152-65535). Well-known ports are reserved for use by specific protocols and applications, registered ports are typically used for custom or third-party applications, and dynamic/private ports are available for use by any application.
Here are some of the most common network ports and their associated protocols:
- Port 80: HTTP (Hypertext Transfer Protocol)
- Port 443: HTTPS (Hypertext Transfer Protocol Secure)
- Port 22: SSH (Secure Shell)
- Port 23: Telnet
- Port 25: SMTP ( Simple Mail Transfer Protocol )
- Port 53: DNS (Domain Name System)
- Port 69: TFTP (Trivial File Transfer Protocol)
- Port 8080: HTTP Alternate
- Port 143: IMAP (Internet Message Access Protocol)
