What is port sieciowy?

Port Sieciowy (Network Port)

A port sieciowy (https://www.wikiwhat.page/kavramlar/port%20sieciowy) is a virtual point where network connections start and end. It's a software-defined numerical identifier used by network protocols, allowing multiple applications or services to share a single network connection (typically over IP) on a single device (like a computer or server).

Think of it like apartment numbers in a large building (the IP address). The IP address gets the message to the building, and the port number gets the message to the correct apartment.

Key Aspects:

• Purpose: Used to distinguish between different applications or services running on the same device. Without ports, network traffic would have no way of knowing which application should receive the data.

• Range: Port numbers are 16-bit integers, ranging from 0 to 65535.

• Types:

  • Well-Known Ports (0-1023): These are reserved for common services and applications like HTTP (port 80), HTTPS (port 443), SMTP (port 25), and FTP (port 21). They are typically controlled by the Internet Assigned Numbers Authority (IANA).
  • Registered Ports (1024-49151): Can be used by any application, but they are typically registered with IANA to prevent conflicts.
  • Dynamic/Private Ports (49152-65535): These are temporary ports used by client applications when initiating a connection. They are assigned dynamically by the operating system.

• Protocols: Ports are associated with specific network protocols, such as TCP (https://www.wikiwhat.page/kavramlar/TCP) and UDP (https://www.wikiwhat.page/kavramlar/UDP). The same port number can be used by different protocols, but usually, different services use different port numbers to avoid confusion.

• Socket: A socket (https://www.wikiwhat.page/kavramlar/socket) is an endpoint of a two-way communication link between two programs running on the network. It is typically a combination of an IP address and a port number.

• Firewalls: Firewalls (https://www.wikiwhat.page/kavramlar/firewall) use port numbers to control network traffic. They can be configured to allow or block traffic based on the source or destination port.

In summary: Port numbers are essential for directing network traffic to the correct application or service on a device, enabling multiple applications to use a single network connection simultaneously. Understanding them is crucial for network administration, troubleshooting, and security.