Definition - What does Port Triggering mean?
Port triggering is a process through which a specific outgoing traffic/process targeted toward a port on an external computer/server sends or communicates back to the internal/host node’s port. Port triggering is a type of port forwarding technique that opens up an internal port only when it’s required and for the duration of the session.
Techopedia explains Port Triggering
Port triggering is primarily a method for automating the port forwarding process on an as-needed basis, rather than creating a permanent path for it. It is configured at the gateway router that manages all incoming/outgoing traffic. Typically, port triggering is implemented in network applications/services to ensure port or network security as a whole.
For example, an application from the local network device may attempt to access a remote/external server on any specific port. In return, the remote/external server sends back a request targeted toward a specific port on the local device, at which point the remote/external server will verify the identity of the local device by initiating a connection or communication with it. Once this is done, the server sends in the requested data or process. In the case of a non-configured gateway, the new connection from the remote server will be rejected.