For a complete security camera surveillance system, video recorder is a crucial device for you to view live streaming video and record down large amount of video data for playback to get critical evidence in the future. NVR, stands for network video recorder, is an advanced video recorder for IP cameras. For beginners who intend to employ NVR, knowing about specification of the NVR is definitely not so easy. While you diving in the world of choosing suitable NVR for your security camera surveillance system, you may encounter the terms of dual HDMI and dual Ethernet ports. Today, we will focus on these two not so common functions, helping you to learn about what are they and what can you benefit from them.

You should know that NVR only functions as storage, thus you need media to display camera’s video, and these media is together called monitor. You can choose to use TV monitor, computer monitor, or even smart phone monitor. For connecting these monitors, HDMI port is the bridge between NVR and monitor. You can find it easily in various NVRs. Then you may confused about HDMI, it is the abbreviation of High-Definition Multimedia Interface, a common format for transferring video/audio data between devices. Rely on this, you are able to get high quality video image with audio together on monitor supports HDMI. As a matter of fact, the NVR is also equipped with a VGA port for connecting analog camera and only can receive video data. In this way, you are capable to integrate IP camera with analog camera in your surveillance system, giving you great flexibility to employ cameras at locations require high definition image quality from IP cameras or relative low image quality from traditional analog cameras. This is quite useful to reduce budget on the whole, as you can choose to use the cheaper analog cameras at locations call for less requirement on extreme clear image.
Let’s get back on track, as more and more manufacturers of NVR attempt to produce upper grade NVR according to demands of customers and actual applications. Dual HDMI comes out and becomes more universal in practical application. For instance, you want to split cameras on two separate monitors. Fortunately, this function enables you to get two HDMI outputs, that said you are able to split cameras and display on two separate monitors support HDMI. More importantly, it is different from the above mentioned NVR designed with one HDMI port and one VGA port, as the video display on the two monitors are from the same cameras, whereas dual HDMI allows you to display several channels of live streaming cameras on the second monitor separately. Therefore, you can get larger video display of some relatively important monitor areas to see the details clearly. This provide you great flexibility to monitor specific cameras at one room and other cameras at another room, giving clearer responsibility division for managers take charge of the camera surveillance system and easier control and management. One thing to be noted, only camera connecting to HDMI1 port is equipped to activate recording function for smart event playback. Besides, dual HDMI can remain live streaming of cameras split to HDMI2. All the operation on the HDMI1 monitor don’t affect HDMI2 monitor. In addition, some more advanced NVRs are not only equipped with dual HDMI but also offer you chance to integrate analog camera into the surveillance system, so you will also find a VGA port on those NVRs.

Reading to here, I believe you have some basic knowledge of dual HDMI, in the following, we are going to talk about more complicate term, that is dual Ethernet ports, also called dual nics.
As its name implied, you are able to find dual Ethernet ports on those NVRs. There is no denying that NVR(Network Video Recorder) needs to connect to network, which can receive by connecting to Ethernet switch or router directly. However, you may confuse, for getting network, one Ethernet port is enough, why being trouble to add one more Ethernet port? Actually, dual Ethernet ports design make great sense on practical application, especially for businesses requiring high security, extreme reliability and clear division of responsibility.
You are supposed to keep in mind that before activating dual Nics, it is essential to keep two Ethernet ports connect to different gateway otherwise the two ports fail to work under this condition and your NVR won’t send any alert either. Let’s get down to several functions from which most of you can benefit, namely, multi-address, load balance and fault tolerance.
Multi-Address
Multi-address allows you to segregate the network. With dual Nics, your network will be divided into two different gateway after easy configuration. In other word, one Ethernet port mainly used for IP surveillance system, and the other port connect to your original network that server the whole networking system of your business. How this can do good to you? This function does helpful to get a clear division of responsibility because the surveillance system is totally work under a separate network, that means if any occurrence of loss caused by network security, you can know whether it is to blame new adding surveillance system or not. One thing should noted, you should not only to make sure the two Nics use two different gateway, while you utilize this function, your cameras also should stay in different IP address under the same gateway, or both ports won’t work normally.


Load Balance
As to load balance, it can simply perceived as a way to plus the amount of network data rate of two Ethernet ports, so using dual Nics of the NVR is practical to ease the load of video data transmission and provide higher bandwidth for the operation of security cameras surveillance system, which is useful for those application requires great network speed in particular. For instance, provided your Ethernet switch or PoE switch equips with 1 Gigabit Ethernet ports, then employ dual Ethernet ports, you will get two Gigabit network speed in total. This load balance function offers option to solve low bandwidth problem especially when your switch only support 10/100Mbps network rate.
Fault Tolerance

The last but not the least, in terms of fault tolerance, it seems hard to understand its meaning and find its benefit. While as a matter of fact that this function is used to provide a more stable security camera surveillance system by giving you chance to tolerate fault issues like the connecting switch stops working in a sudden. That means the whole surveillance system fails to work meanwhile. This might result in serious property loss or safety risk potentially if the camera system can’t be work continuously, it is particular when accident occur at night as you even can’t find the system failed timely. With two Ethernet ports, you are able to add one more switch works as a backup system, one fails, one still works.
Hope these information can give you an overall knowledge to NVR’s dual HDMI and dual Ethernet ports. You are supposed to own one to take advantages of its multiple functions. Try to get one now.