Reolink products support both LAN and WAN connections. Check below for more information about these 2 kinds of connections.
Applies to: All Reolink cameras and NVRs
It means local area network. For example, in your home, all the devices are connected to the same router. The network under your router is a LAN.
If your devices (phone/PC) and the camera are on the same LAN, then you don't need the Internet to connect to the camera/NVR.
For a more detailed definition of LAN, please check Local area network.
It means a wide area network. For example, in your home, the network under your router is a LAN, and the network outside your router (your ISP's network) is a WAN. Compared to LAN, WAN is a much larger network. And the Internet is the largest WAN.
And if you want to connect to the camera/NVR in a WAN, it requires that your camera/NVR (LAN) is connected to the Internet.
For a more detailed definition of WAN, please check Wide area network