Ports

A port is part of the IP address. Ports are used to communicate between 2 or more computers with the Internet. For this purpose, data packets are sent to an IP address and specifically assigned to an application or service through certain ports. The ports, numbered consecutively from 0 to 65535, are also divided into 3 groups. The standard ports from 0 to 1023 are the most important ports and are all linked to specific services, such as websites. These port numbers of this group are assigned by the IANA. The port numbers 1024 to 49151 belong to the user port group and are also assigned to certain services (e.g. for the management of networks). The dynamic ports form the last port numbers up to 65535. The allocation of the port numbers depends on the operating system. To protect the computer from viruses, unused ports are automatically closed by a firewall on the computer.