When network devices are connected to a network, IP address conflicts may occur. This happens because two devices are configured with exactly the same IP address. This situation is frequently encountered in daily maintenance work. Today, we will briefly explain how to avoid this problem.
How to Avoid IP Address Conflicts in Network Cameras
The way network cameras obtain IP addresses is similar to computers. There are two methods:
one is manually setting the IP address, that is, a static IP address;
the other is dynamically obtaining an IP address, that is, a dynamic IP address.
Static IP address: the camera’s IP address is fixed and does not change.
Dynamic IP address: the IP address is dynamically assigned by a device with DHCP capability in the network (such as a common wireless router).
1. Static IP Address
When using static IP addresses, IP planning for all devices should be completed before installing the surveillance equipment. It is recommended that the surveillance network be physically isolated or logically isolated from the internal office network, to prevent other network terminals from manually changing IP addresses, which may cause IP conflicts and result in surveillance video interruption or intermittent loss.
1) Physical isolation
Physical isolation means that the surveillance system operates in a separate network.
For example, the office network connects to one router, and the surveillance network connects to another router.
If the network scale is small, refer to: Methods for solving frequent disconnection of small surveillance systems caused by IP address conflicts by configuring a wireless router.
2) Logical (virtual) isolation
Logical isolation is achieved by configuring DHCP on the switch (preventing network terminals from manually changing IP addresses) and by configuring VLANs (unauthorized devices cannot access the surveillance network system).
In this case, although the surveillance system and the office system are physically in the same network, access permissions between devices are controlled.
Note: Surveillance equipment manufacturers usually provide IP address management tools, which make it convenient to configure camera IP addresses.
2. Dynamic IP Address
In addition to switches and routers having DHCP functions, network video recorders (NVRs) also have DHCP functionality.
If a camera is set to obtain an IP address dynamically, when it fails to obtain an IP address from the switch or router, it may obtain an IP address from the NVR. This can cause network interruption. Therefore, it is recommended to disable the DHCP function on the NVR.
For example, in very small surveillance systems (such as home use), cameras are usually connected directly to a wireless router or to a switch cascaded from it. At the same time, mobile phones and other wireless terminal devices are also connected to this router. When these devices connect to the network, they dynamically obtain IP addresses in sequence.
Note: Dynamic IP addresses have a lease time, which can be understood as a validity period. When this lease expires and the device is offline, the IP address will be reclaimed and made available for other devices.
A common situation is a sudden power outage. After the devices restart, a mobile phone may obtain an IP address that was previously used by a camera. After this address is occupied, the camera will obtain a new IP address. However, the camera IP channel address configured in the NVR does not change. As a result, the IP address stored in the NVR is now used by the mobile phone, which causes surveillance video interruption or channel order confusion.
3. Troubleshooting IP Address Conflicts
1) IP address conflicts between cameras
If the cameras and the NVR are from the same brand, the camera IP address can be modified directly through the NVR.
If they are not from the same brand, the camera manufacturer’s configuration tool can be used to modify the IP address.
2) IP address conflicts between cameras and other network terminals
Since other network terminals may not be within a controllable range, IP conflicts can only be avoided by properly configuring the camera IP addresses.