In the rapidly popularized era of smart homes, how to create an efficient, stable, and easy to manage network has become the key to achieving a convenient experience in smart homes. PoE (Power over Ethernet) switches, as an innovative network device, are gradually emerging and providing an ideal solution for connecting smart home devices.
1、 What is a PoE switch
PoE switches, also known as Power over Ethernet switches, have a unique ability to simultaneously transmit data and power over Ethernet cables. This means that devices connected to PoE switches, such as wireless access points (APs), IP cameras, smart speakers, etc., can achieve data communication and device power supply simultaneously with just one Ethernet cable, completely bidding farewell to the complex situation of power lines and network cables working independently in traditional cabling.
2、 Working principle of PoE switch
The workflow of a PoE switch can be roughly divided into the following key steps:
Detection: When a device is connected to a PoE switch port, the switch will immediately detect whether the device is a powered device (PD) that supports PoE technology. If the detection result is yes, proceed to the next step; If not, the switch only performs data transmission and does not provide power.
Classification: After confirming that the device is PD, the PoE switch will evaluate its required power level and accurately allocate power based on the evaluation results to ensure that the device can obtain sufficient power without being damaged by excessive power supply.
Power supply: Based on the classified information, PoE switches provide stable power to PD devices through Ethernet cables in a specific manner (such as using idle line pairs to transmit DC power using the "intermediate jumper method" and transmitting DC power simultaneously on the data core line using the "end jumper method").
Power outage: Once the PD device no longer needs power or is removed from the port, the PoE switch will automatically stop supplying power, effectively avoiding energy waste.
3、 The advantages of PoE switches in smart homes
Simplified wiring:
There are numerous smart home devices, and under traditional wiring methods, power cords and network cables are interwoven, which can easily cause cable clutter. This not only affects aesthetics but also increases the difficulty of installation and maintenance. PoE switches achieve data and power transmission through a single Ethernet cable, greatly reducing the number of cables and making wiring work simple and orderly. Whether it is early installation or later troubleshooting, it is more convenient.
Enhance device flexibility:
There is no need to separately find power sockets for each device, as long as the devices are within the effective power supply range of the PoE switch, they can be flexibly deployed. Taking wireless AP as an example, the installation location can be freely selected according to the actual layout and signal coverage needs of the home, easily achieving seamless coverage of Wi Fi throughout the house and completely freeing itself from the constraints of power location.
Centralized management and maintenance:
PoE switches can centrally manage connected devices, and through the management interface, real-time monitoring of device power status, data transmission status, etc. can be achieved. Once the device malfunctions, the problem can be quickly located and repaired. For example, when an IP camera malfunctions, it can be directly checked on the switch management interface to see if its power supply is normal and if the network connection is stable, greatly improving maintenance efficiency.
Improving network stability:
Compared to wireless connections, wired connections are less susceptible to interference factors and can provide more stable and reliable network transmission for smart home devices. PoE switches provide stable power to devices while ensuring efficient and stable data transmission, effectively reducing network lag, disconnection, and other situations, ensuring the smooth operation of smart home systems. For example, high bandwidth applications such as 4K video surveillance and online gaming can receive continuous and stable network services with the support of PoE switches.
4、 Connection scheme of PoE switch in smart home
Basic connection scheme
Equipment preparation: Select the appropriate number of ports and PoE power supply switch based on the number of smart home devices and port requirements. For example, if there are 5 wireless APs, 3 IP cameras, and 2 smart speakers at home, you can choose a 16 port PoE switch with a total power supply that meets the device's requirements. Meanwhile, prepare high-quality Ethernet cables such as Cat.5e or Cat.6 Ethernet cables to ensure stable data transmission and power supply.
Connection steps: Firstly, place the PoE switch in a well ventilated and easily manageable weak current box or suitable location, and connect the power supply. Next, use an Ethernet cable to connect one end to the POE port of the PoE switch and the other end to the Ethernet interfaces of various smart home devices, such as connecting wireless APs, IP cameras, smart speakers, etc. to the switch port in sequence. After the connection is completed, the device will automatically obtain power and attempt to establish a network connection.
Multi floor or large area housing connection scheme
Serial PoE switch: For multi-layer villas or large area houses, a single PoE switch may not be able to meet the connection needs of all devices. At this point, network coverage and port count can be expanded by connecting PoE switches in series. When performing specific operations, connect the uplink port (Uplink) of the first PoE switch to the router or core switch to ensure that the router can provide DHCP or fixed IP addresses normally. Then, use Ethernet cables to connect the downlink port of the first switch to the uplink port of the second switch. If there are multiple switches, cascade them in this order. Attention should be paid to avoiding the formation of network loops. If a loop structure is used, STP (Spanning Tree Protocol) should be enabled to prevent network failures.
Reasonably allocate ports and power supply: In a multi switch series environment, it is necessary to allocate the devices connected to each switch port according to the distribution of devices and power requirements, and set appropriate power supply for different device ports in the management interface. If wireless APs and some smart sockets are mainly arranged on the first floor, and security cameras are emphasized on the second floor, corresponding power can be allocated to these device ports on the corresponding switches. For example, cameras usually require 15W-30W, and wireless APs may require higher power. At the same time, to avoid broadcast storms and bandwidth competition, it is recommended to enable VLAN (Virtual Local Area Network) function, which divides different services into independent VLANs to improve data isolation; And configure QoS (Quality of Service) to assign high priority to critical services such as video surveillance and voice communication, ensuring smooth data transmission.
Connection scheme in conjunction with AC (wireless controller)
AC management AP: In the construction of smart home wireless networks, AC (wireless controller) can be used in conjunction with PoE switches to achieve more efficient wireless management. AC can centrally manage all wireless AP devices, automatically optimize channel allocation, and ensure seamless roaming for users when moving between different APs. PoE switches are responsible for supplying power to AP devices while transmitting data. Firstly, connect the PoE switch to the AC to ensure that the AC can obtain information about the AP devices connected to the PoE switch. Then, configure the AP uniformly in the AC management interface, including SSID settings, password management, channel optimization, etc.
Remote management and energy-saving control: PoE switches support remote management functions, and with AC, network administrators can easily complete device restarts, firmware upgrades, and other tasks through remote operations. In addition, PoE switches also have the advantage of green energy saving. They can provide power to devices at specific times according to actual needs, such as turning off non essential devices at night. Compared with traditional independent power adapters, they can reduce standby energy consumption by about 30%, which is both energy-saving and environmentally friendly, and extends the service life of devices.
5、 Precautions for choosing a PoE switch
Number and Type of Ports: Based on the actual number and type of smart home devices, select a PoE switch with sufficient number of ports and compatible port types. If the device supports both gigabit and 100Mbps networks, a switch with both gigabit and 100Mbps ports can be selected to meet the network needs of different devices.
PoE power standards and power: Ensure that the power standards supported by PoE switches (such as IEEE 802.3af, IEEE 802.3at, IEEE 802.3bt, etc.) are compatible with smart home devices, and that the total power supply of the switch can meet the power requirements of all devices. For example, if multiple devices at home have a total power of 100W, it is necessary to choose a PoE switch with a total power supply greater than 100W to prevent insufficient power supply.
Management function: If you want to finely manage the smart home network, you can choose a PoE switch with rich management functions, such as switches that support VLAN partitioning, QoS settings, port mirroring, etc., to facilitate network traffic optimization, device isolation, and monitoring operations.