What does the term "trunk line" refer to in the context of 3CX?

The term "trunk line" in the context of 3CX refers to a line for external calls. In VoIP systems, including 3CX, a trunk line is used to connect the internal phone system to external telephone networks. This allows users to make and receive calls outside their local network. Trunk lines are crucial for facilitating communication with customers and other external contacts. They effectively serve as the bridge between the internal calling capabilities of the organization and the broader public telephone network.

Other options provide definitions that do not align with the concept of a trunk line. An extension for customer service relates more to individual phone lines set up for specific purposes within the internal system, while a directory of internal extensions would pertain to the internal structure of the phone system itself, listing all the available extensions. A type of software license does not connect to the telephony infrastructure, as it concerns the legal use of software rather than telecommunication connections.