EDIT, for clarification: Let's say that my server listens TCP port 80. A client makes a connection and port 56789 is allocated for it. Then, I discover that this connection is undesired (e.g. this user is doing bad things, we asked them to stop but the connection didn't get dropped somewhere along the way).

Manageability Ports Starting with Release 6.0, the port is optionally open when TLS is enabled. The port is always open locally. See Defining Secure Connection Settings. 16993. Intel(R) AMT HTTPS. Used for WS-Management messages to and from Intel AMT when TLS is enabled. See Transport Layer Security. 16994. Intel(R) AMT Redirection/TCP TCP/IP Ports Required for IBM i Access and Related Functions Feb 19, 2020

networking - How to close TCP and UDP ports via windows

List of Well-Known TCP Port Numbers - Webopedia Reference 48 rows

Ports used for connections - Configuration Manager

A port number is assigned to each end, like an address, to direct the flow of internet traffic. If you’re having trouble connecting to any of our online games — and you have tried basic connection troubleshooting — you may need to open some ports on your network connection. Consoles. To set up TCP or UDP ports for consoles, follow steps for: Port Number Database Search - WintelGuy.com Information Sources: [IANA] IANA Service Name and Transport Protocol Port Number Registry [NMAP] NMAP.org well known service port numbers [WG] WintelGuy.com port number database compiled from many different sources, including Microsoft, VMWare, Citrix, Oracle, etc. [WP] Wikipedia - List of TCP and UDP port numbers [SANS] SANS Inst. / DShield service list What is an SMB Port + Ports 445 and 139 Explained | Varonis