The term DVR refers to a recorder that records a video signal from an analog feed via coaxial cable. Digital in DVR means it is recording to a hard drive. NVRs also use hard drives. The term DVR originated first to distinguish the new hard drive recorders from older VCR recorders. NVR was the term created to distinguish IP camera recorders from analog camera recorders.
Analog camera wiring most often uses a wire called "Siamese wire". Analog cameras are wired with the positive and negative (red and black) wires connect to an external power supply and coaxial cable into the DVR. The video of the “Siamese wire” is often RG6 or RG59 coaxial cable which terminates into a BNC connection.
BNC connections are difficult for non-professionals to install.
An NVR is a recorder that records signals from an IP Camera that transmits its video feed via ethernet wiring. The term IP stands for internet protocol and is a standard for transmitting data on a network. IP Camera wiring uses CAT5/CAT6 ethernet cable from the camera to a PoE port on the NVR, PoE switch, or PoE injector. Most NVRs include Power over Ethernet (PoE) ports that provide power to the camera while at the same time transmitting data.
Ethernet jacks (RJ45) on CAT5 wiring are much easier to attach than BNC jacks on coaxial cable. Due to the prevalence of CAT5 wiring for all things networking related it is also very easy to find pre-made cables in your required length.
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