When signaling occurs over a separate path from the analog voice signal, it is known as?

The concept of signaling that occurs over a separate path from the analog voice signal is referred to as out-of-band signaling. This means that the signaling information, which controls the establishment, direction, and teardown of a communication session, travels on a different channel rather than being intermingled with the voice signals themselves.

Out-of-band signaling is often more efficient and reliable because it can be transmitted over a dedicated control channel, allowing for faster setup times and improved management of calls. This separation ensures that the signaling can continue without disruption even if the voice path encounters issues, providing greater flexibility and robustness in communication systems.

The other options—such as in-band signaling, where control information is sent within the same channel as the voice signal, or parallel signaling, which typically refers to methods of data transmission rather than signaling in telecommunication contexts, and digital signaling, which concerns the representation of signals—do not accurately describe the situation outlined in the question. Thus, out-of-band signaling is the correct choice to indicate a separate path for signaling compared to analog voice signals.