IP Security Camera Glossary & Expert Guide (PoE, NVR, Network Terms)
Learn the most important terms used in security cameras, PoE security camera systems, and IP surveillance—including PoE, NVR, IP cameras, storage, and network basics. Use this guide to choose the right system with no monthly fees and reliable 24/7 local recording.
PoE (Power over Ethernet)
PoE sends power and data over one Ethernet cable (Cat5e/Cat6). This makes wired IP cameras easier to install and more reliable than Wi-Fi cameras.
Why it matters: PoE reduces failure points, avoids local power at the camera, and supports stable 24/7 recording to an NVR with no monthly fees. Shop PoE IP systems.
IP Camera (Network Camera)
An IP camera is a digital security camera that transmits video over a network (Ethernet) to an NVR.
Why it matters: IP cameras support higher resolution (HD/4K), advanced analytics, and scalable system design. Browse SureVision IP cameras.
NVR (Network Video Recorder)
An NVR records video from IP cameras to internal hard drives for secure local storage, playback, and remote access.
Why it matters: Local NVR recording provides consistent evidence, longer retention, and avoids cloud subscription costs. Shop SureVision PoE NVRs.
H.264 / H.265 (Video Codec)
A codec compresses video so it can be stored and streamed efficiently. H.265 typically reduces file size versus H.264 at similar quality.
Why it matters: Better compression can increase retention time on your NVR and improve remote viewing performance.
Bitrate
Bitrate is the amount of data used to encode video (often measured in Kbps/Mbps). Higher bitrate usually means better detail—but uses more storage.
Why it matters: Bitrate is one of the biggest drivers of storage retention. It also affects clarity in motion scenes like parking lots and entrances.
Storage Retention (Days of Recording)
Storage retention is how many days of video your NVR can keep before overwriting older footage.
Why it matters: Retention depends on camera count, resolution, bitrate, codec, and whether you record 24/7 or motion-only. Planning retention correctly helps avoid missed evidence.
WDR (Wide Dynamic Range)
WDR improves visibility when a scene has bright and dark areas—like a lobby with sunlight or a doorway facing outside.
Why it matters: WDR helps capture faces and details instead of silhouettes in high-contrast lighting.
Night Vision (IR)
IR night vision uses infrared LEDs to see in low-light and darkness. Range is typically measured in feet/meters.
Why it matters: Real surveillance requires clear night performance for driveways, parking lots, and perimeters—where incidents often happen.
Varifocal Lens (Motorized Zoom)
A varifocal lens can zoom in/out to adjust field of view. Motorized varifocal makes it easy to fine-tune identification distance.
Why it matters: Varifocal lenses are ideal when you must capture faces, plates, or details at a specific distance.
ONVIF
ONVIF is an interoperability standard that helps IP cameras and recorders communicate across compatible devices.
Why it matters: Standards matter, but best results come from using matched cameras + NVR built to work together.
AI Detection (Human / Vehicle)
AI detection filters alerts by recognizing people and vehicles—reducing false notifications from shadows, rain, or trees.
Why it matters: Better alerts = faster response and easier search when reviewing incidents.
NDAA Compliance
NDAA compliance refers to meeting U.S. government requirements that restrict certain manufacturers in federal installations.
Why it matters: If you work with government, schools, or regulated projects, compliance can be mandatory when specifying cameras and NVRs.
