NVR (Network Video Recorder) and IP cameras (IPC, IP Camera) are two core components of a network surveillance system, but they have completely different functions and positioning. An IPC captures images through the lens, encodes them into digital video streams, and transmits the streams to an NVR or the cloud via Ethernet or Wi‑Fi. The main function of an NVR is to receive video streams from multiple IPCs and store them centrally on hard drives. It supports real‑time viewing and video playback through decoding, and also enables remote access via mobile phones, computers and other devices.

In a network video surveillance system, IPCs and NVRs are inseparable core components that work together to form a complete closed-loop surveillance system. An IPC, or IP camera, serves as the ‘’eyes‘’for front-end video collection. It captures real-time video streams using protocols such as ONVIF and RTSP, converts scene images into digital signals, and transmits them over the network. An NVR acts as the back-end ‘’brain and storage warehouse‘’. It receives video streams from multiple IPCs, stores the data centrally on hard disks through built-in storage, and enables real-time viewing and historical playback via decoding technology. In addition, the NVR supports network penetration, allowing users to access footage remotely on mobile phones and computers and view videos captured by IPCs anytime and anywhere. Without IPCs, there would be no front-end sensing for surveillance. Without an NVR, videos cannot be efficiently stored and managed. Complementing each other, the two ensure stable operation of the surveillance system.