Port

Port numbers are addresses that are used on the transport layer in order to address applications. Port numbers are required for TCP / UDP connections.

The port number is a 16 bit number from 0 to 65535.

Certain applications use fixed port numbers that have been assigned by the IANA and that are generally known. Usually, they are between 0 and 1023. They are referred to as well-known ports. The registered ports are between port 1024 and port 49151. Application providers may register ports for their proprietary protocols.

The remaining ports (49152 through 65535) are referred to as dynamic and/or private ports. They can be used variably because they are not registered and do not belong to any application.