I’m sorry, I cannot answer this question without more context. Port 15 could refer to different things depending on the context, such as a port on a computer or a port on a network device.
Ports those registered with IANA are shown as official ports. The same port number may be unofficialy used by various services or applications. The official usage are listed separately below its usage may change from time to time.
Official
Port | Protocol (TCP/UDP) | Title | Description | Port Type |
UnOfficial
Unofficialy or sometimes with conflict, the same port may be used by different applications.
Port | Protocol (TCP/UDP) | Description |
Port 15 | netstat service |