Many of today’s IP camera models include built-in audio support so you can listen in on areas under surveillance and even communicate directly with those in range of the camera. Audio can be an invaluable tool for a variety of applications, for instance video conferencing, communicating with visitors and intruders, and integrating pre-recorded messages for use with access control. Analog CCTV systems require separate cables and equipment for audio, while an IP camera sends both video and audio over the same network cable.