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An NVR is the device that receives video streams from IP cameras over an Ethernet network and saves them to a hard drive. Instead of physically visiting a site to pull footage, a manager opens the NVR’s web interface – from anywhere – and searches by camera, time, and event.
NVRs replaced DVRs as surveillance systems moved to IP cameras. Unlike DVRs, NVRs never touch analogue signals – everything is encoded video over Ethernet, which means higher resolution, AI analytics, and multi-site access are all standard features.
- ONVIF compatibility – an ONVIF-certified NVR works with ONVIF-certified cameras regardless of brand
- AI analytics – modern NVRs run people counting, face detection, and VCA without a separate server
- Remote access – accessible via web browser, mobile app, or VMS client from any location
- Storage sizing – rough formula: (bitrate per camera × number of cameras × seconds per day × retention days) ÷ 8,000,000,000 = TB required