Devices in a PoE network can be divided into two categories: PoE power supply equipment (PSE) and PoE powered device (PD). Among them, there are many types of PoE powered devices, such as IP phones, IP cameras, wireless access devices, Video phones, video conferencing equipment, etc., and the types of PoE power supply equipment are relatively less, mainly including PoE switches, PoE power supplies, PoE network video recorders and PoE fiber optic transceivers. In addition, PoE splitters are also commonly used to facilitate the integration of devices that do not support PoE power supply into PoE networks.
1. PoE switch
A PoE switch is a network switch that supports Power over Ethernet (PoE). It can not only realize the data transmission function of ordinary switches, but also supply power to terminal PoE powered devices at the same time.
2. PoE Injector
The PoE power supply can only supply power to PoE powered equipment through the network cable, without the data processing and filtering functions of the switch. Its main function is to inject its own power and data signals from ordinary switches into the network cable and transmit them to the terminal PoE powered equipment.
PoE network video recorder is a video recorder with power over Ethernet function, which is mainly used in IP video surveillance system and is responsible for the storage and forwarding of video streams. After the PoE camera and PoE network video recorder are connected through a network cable, DC power supply and data transmission can be performed at the same time, without additional power supply to the camera.
4. PoE Fiber Optic Transceiver
The PoE fiber optic transceiver is to add the function of power supply over Ethernet to the ordinary fiber optic transceiver. Therefore, it can not only convert the short-distance twisted pair electrical signal Wait for the PoE powered device to supply power.
5. PoE Splitter
PoE splitter is also a kind of power supply equipment. It is mainly used in the occasion where the upper end is PoE switch, PoE power supply and other PSE equipment, and the lower end is non-PoE equipment. Its function is just the opposite of PoE power supply, which is to separate data signal and power. , and then use network cables and power cables to transmit to non-PoE devices.
6. Comparison of PoE power supply equipment: PoE switch vs. PoE injector vs. PoE network video recorder vs. PoE fiber optic transceiver
Among the above four types of PoE power supply equipment, PoE switches are the most commonly used products. It has the advantages of cost saving, convenience and high efficiency, etc., and is the first choice for PoE power supply equipment for deploying PoE networks in homes and offices. Nevertheless, PoE injectors, PoE network video recorders and PoE fiber optic transceivers are still frequently used by people due to their own advantages.
6.1 PoE switch vs. PoE injector: When can a PoE injector be used?
Before the popularity of PoE switches, ordinary switches without Power over Ethernet function were used in home and enterprise networks. What should we do if we need to add some PoE powered devices to these networks? Replacing ordinary switches with PoE switches is a feasible method, but it is undoubtedly more expensive. In fact, it is only necessary to equip each PoE powered device with a PoE injector to solve this problem, because the PoE injector is specially designed for the situation where there is no PoE switch but a small number of PoE powered devices in the network. It should be noted that if there are a large number of PoE powered devices in the network, using a PoE switch will be a more cost-effective solution.
6.2 PoE switch vs. PoE network video recorder: under what circumstances can a PoE network video recorder be used?
In the IP surveillance system, the PoE network video recorder acts as both the video recorder and the PoE switch. Therefore, if the PoE network video recorder is used, there is no need to equip the PoE camera with a PoE switch. However, PoE network video recorders lack management functions such as device control and Simple Network Management Protocol (SNMP) of PoE switches, and are only suitable for use in small PoE monitoring networks that require less network management.
6.3 PoE switch vs. PoE fiber optic transceiver: under what circumstances can a PoE fiber optic transceiver be used?
We know that without using a PoE network extender, the data transmission and power supply distance of a PoE switch is usually only 100 meters. The PoE fiber optic transceiver can break through this limitation. It connects the fiber optic network to the copper wire Ethernet through the optical port to extend the distance, and then injects the data signal and its own power into the network cable and transmits it to the IP phone, IP camera, etc. PoE powered equipment. It should be noted that the PoE fiber optic transceiver does not have the data processing function of the switch, so a common network switch needs to be configured in the network.
6.4 PoE Injector vs. PoE Splitter: When is PoE Splitter Needed?
As mentioned above, the functions of PoE splitter and PoE power supply are exactly the opposite. It is generally used at network terminals to separate PoE signals into data signals and power signals and send them to non-PoE devices respectively. In a PoE network, PoE splitters and non-PoE devices together form PoE powered devices (for example, PoE splitter + IP camera = PoE IP camera).