What is defined as a physical line for transmitting 911 audio?

The definition of a physical line for transmitting 911 audio refers specifically to a channel. A channel is a designated path through which audio signals, such as 911 calls, are transmitted. In this context, the channel ensures clear and reliable communication by providing a dedicated route for the audio data to travel from the caller to the dispatch center.

A trunk typically refers to a larger-capacity line that connects multiple calls or channels in telecommunications but does not specifically denote the individual line for 911 audio. Bandwidth describes the capacity of a channel to transmit data but does not define a physical line itself. A line switch refers to the equipment used to manage and route calls but doesn't specifically indicate the transmission line for audio. Thus, the most accurate term aligning with the definition of a physical line for transmitting 911 audio is a channel.