TCP, UDP, and SCTP all use port numbers to identify the logical communications between hosts. The combination of a port and IP address identifies a TCP/UDP/SCTP Endpoint, and the endpoint pairs on either end of a "connection" make up a TCP/UDP/SCTP Conversation.
The concept of a TCP/UDP port is to provide several logical channels between the same IP hosts. When sending a packet, TCP/UDP multiplexes the data from separate applications over one IP "host to host transfer". While receiving, TCP/UDP demultiplexes the IP packets again, providing the received data to the applications interested in.
The addressing of this multiplexing/demultiplexing is done using the ports.
- 0 through 1023: Well Known Ports
- 1024 through 49151: Registered Ports
- 49152 through 65535: Dynamic or Private Ports
o the System Ports, also known as the Well Known Ports, from 0-1023 (assigned by IANA) o the User Ports, also known as the Registered Ports, from 1024- 49151 (assigned by IANA) o the Dynamic Ports, also known as the Private or Ephemeral Ports, from 49152-65535 (never assigned)
Ports 1024 and above are also referred to as ephemeral ports.
Ports are officially registered with the IANA. Unofficial lists are maintained by many people, including the following:
A local list is maintained below:
Imported from https://wiki.wireshark.org/PortReference on 2020-08-11 23:18:00 UTC