What is Power over Ethernet

As we all know, there are two different IP cameras. One need connect external power supply and network cable. Another just need connect network cable only as long as you have POE switch on hand. Now, we want to explain the principle for you. Power over Ethernet (POE) is a technology that lets network cables carry electrical power. The Power over Ethernet feature － the IEEE 802.3af standard － lets Ethernet cables supply the power for network devices, at the same time as transmitting data in the normal way. Typical PoE users are businesses adding to their network or adding VoIP phones in buildings where new power lines would be expensive or inconvenient.

For example, a digital security camera normally requires two connections to be made when it is installed:
A?network connection, in order to be able to communicate with video recording and display equipment
A power connection, to deliver the electrical power the camera needs to operate
However, if the camera is POE-enabled, only the network connection needs to be made, as it will receive its electrical power from this cable as well.

Power over Ethernet brings many advantages to an installation:
Time and cost savings - by reducing the time and expense of having electrical power cabling installed.? Network cables do not require a qualified electrician to fit them, and can be located anywhere.
Flexibility - without being tethered to an electrical outlet, devices such as IP cameras and wireless access points can be located wherever they are needed most, and repositioned easily if required.

Safety- POE delivery is intelligent, and designed to protect network equipment from overload, underpowering, or incorrect installation.
Reliability - POE power comes from a central and universally compatible source, rather than a collection of distributed wall adapters. It can be backed-up by an uninterruptible power supply, or controlled to easily disable or reset devices.

Scalability - having power available on the network means that installation anddistribution of network connections is simple and effective.