A system of a network video recorder device for automatic connection to an Internet protocol camera, the system comprising: an IP configuration unit configured to automatically allocate to the NVR device a non-duplicate IP address within a valid IP address range; and a communication unit configured to transmit a camera response request information to the IP camera and receive a camera response information from the IP camera; a camera searching unit configured to broadcast to an IP camera on a local area network the camera response request information having as a destination the IP address automatically allocated to the NVR device and to identify the IP camera in response to receiving camera response information transmitted from the IP camera; a camera managing unit configured to analyze the camera response information from the IP camera identified by the camera searching unit to determine whether the IP camera is available to be registered and to, if the IP camera is determined as available, register the IP camera; characterized in that the system further comprises a security level managing unit configured to control a security level of a registered IP camera, wherein the security level managing unit transmits a security level setting request information to an IP camera which is not to be exposed to another NVR device, so as to request the IP camera to set its security level for not responding to a camera response request information broadcast from the other NVR device, and wherein when an IP camera is disconnected while having its security level set so as not to respond to camera response request information broadcast from another NVR device, the camera managing unit initializes the IP camera settings in order to allow the IP camera to be available to other NVR devices. an IP configuration unit configured to automatically allocate to the NVR device a non-duplicate IP address within a valid IP address range; and a communication unit configured to transmit a camera response request information to the IP camera and receive a camera response information from the IP camera; a camera searching unit configured to broadcast to an IP camera on a local area network the camera response request information having as a destination the IP address automatically allocated to the NVR device and to identify the IP camera in response to receiving camera response information transmitted from the IP camera; a camera managing unit configured to analyze the camera response information from the IP camera identified by the camera searching unit to determine whether the IP camera is available to be registered and to, if the IP camera is determined as available, register the IP camera; characterized in that the system further comprises a security level managing unit configured to control a security level of a registered IP camera, wherein the security level managing unit transmits a security level setting request information to an IP camera which is not to be exposed to another NVR device, so as to request the IP camera to set its security level for not responding to a camera response request information broadcast from the other NVR device, and wherein when an IP camera is disconnected while having its security level set so as not to respond to camera response request information broadcast from another NVR device, the camera managing unit initializes the IP camera settings in order to allow the IP camera to be available to other NVR devices.