In the current era of rapid popularization of the Internet of Things (IoT) and smart devices, Power over Ethernet (PoE) technology has become the core support for building efficient network infrastructure. As a leading global provider of PoE solutions, Newbridge has always been committed to driving industry development through technological innovation. Our full range of PoE switches are deeply compatible with the IEEE 802.3af/at/bt standards, providing enterprise level users with a full scenario power supply solution from low-power to high-power devices. This article will analyze the evolution logic of the PoE standard and the core advantages of Newbridge products from the perspectives of technical principles, compatibility mechanisms, and industry applications.
1、 Evolution of PoE Standard: Technological Iteration from Basic Power Supply to Full Power Coverage
PoE technology synchronously transmits data and power through Ethernet cables, and its standard system continues to upgrade with device power requirements, forming three core specifications:
IEEE 802.3af (PoE, published in 2003)
As the foundational standard of PoE technology, 802.3af provides a maximum power supply capacity of 15.4W through two pairs of twisted pair cables (actual available power is about 12.95W), mainly meeting the needs of low-power devices such as IP phones, basic wireless APs, and ordinary network cameras. Despite its high technological maturity, it still maintains stable applications in scenarios such as smart office and educational informatization.
IEEE 802.3at (PoE+, upgraded in 2009)
The PoE+standard increases the single port power supply capability to 30W and supports four wire power supply mode (100BASE-T4), which can drive high-power devices such as high-definition PTZ cameras, dual band wireless APs (such as 802.11ac), and digital signage. Through the physical layer classification protocol, PoE+devices can dynamically negotiate power requirements with PSE (power supply equipment) to ensure seamless compatibility with 802.3af devices.
IEEE 802.3bt (PoE++, updated in 2018)
As the latest standard, 802.3bt introduces two power supply levels, Type 3 (60W) and Type 4 (100W), to achieve higher power transmission through four pairs of wires:
Type 3: Suitable for medium power devices such as multi band 5G wireless base stations, 4K video conferencing terminals, industrial IoT gateways, etc;
Type 4: It is specially designed for industrial robots, LED intelligent lighting, edge computing servers and other 100W high power consumption devices.
802.3bt innovatively adopts Autoclass technology to dynamically adjust power reservation based on actual link length, optimizing the traditional 100 meter fixed loss into real-time calculation, greatly improving energy utilization efficiency.
2、 Newbridge PoE Switch: Triple technology ensures cross standard compatibility
Newbridge has been deeply involved in PoE technology for over ten years, and its switches achieve full compatibility with the af/at/bt standards through a triple mechanism of hardware design, protocol adaptation, and intelligent management
Full protocol hardware architecture
The device is equipped with a self-developed NB PowerCore intelligent power supply chip, which supports voltage detection (15-20V) and power negotiation according to af/at/bt standards, and can automatically identify PD (power receiving device) types:
Automatically output 15.4W power when detecting 802.3af devices;
When identifying 802.3at devices, enable four wire power supply and allocate up to 100W of power, while being backward compatible with the 30W requirement of 802.3at devices.
Dynamic power negotiation mechanism
Layer 1 Classification: By sending specific voltage signals, the power level (Class 0-8) is determined based on the current response (0.4-4mA) of the PD. For example, Class 8 corresponds to 100W devices, and Class 4 corresponds to 30W devices;
Data Link Layer Optimization (LLDP protocol): By discovering the protocol at the link layer, the actual power consumption of the device is confirmed twice to avoid "over supply" or "power shortage", ensuring that the power supply accuracy error of each port is less than 5%.
Intelligent Power Management System
When the total power consumption exceeds the switch capacity, Newbridge's unique PrioritGuard priority management technology allocates power based on port importance:
Critical level (such as security cameras): Priority is given to ensuring full power supply;
High level (such as wireless AP): dynamically adjust to the optimal power;
Low level (such as IP phone): Enter energy-saving mode when resources are tight.
In addition, the device supports PowerPool power pool technology, which can dynamically allocate the remaining power of idle ports to high demand devices, increasing resource utilization by more than 30%.
3、 Scenario based application: Industry wide PoE power supply solution
Smart Business Complex: A Model of Multi Device Hybrid Power Supply
A 5A level office building in Shanghai has deployed a Newbridge 24 port full gigabit PoE switch (NB PoE24G, single port supports 90W) to uniformly power the following devices:
802.3af devices: 32 IP phones (each with 10W);
802.3at devices: 16 dual band wireless APs (each with 25W);
802.3bt devices: 8 4K facial recognition cameras (each 60W).
Through the automatic protocol recognition function of the switch, cross standard compatibility can be achieved without manual configuration, reducing deployment costs by 40% and energy consumption by 25% year-on-year.
Industry 4.0 production line: high reliability power supply solution
A certain automotive electronics factory in Zhejiang Province uses Newbridge 16 port PoE industrial switch (NB-IP67PoE, supporting -40 ℃~75 ℃ wide temperature range) to connect 200+industrial sensors and robotic arm controllers:
Assign dedicated high-power ports to Type 4 devices (robotic arm drivers, 80W);
Dynamically adjust the power supply mode for Type 2 devices (RFID reader/writer, 20W);
By using link redundancy protection (ERPS) and overload current limiting technology, critical equipment can continue to operate during power grid fluctuations, reducing production line failure rates by 60%.
Smart City Security: Long Range High Stability Deployment
In a county-level smart city project, Newbridge 8-port PoE++switch (NB PoE8G-PLUS, single port 100W) is used for remote area monitoring:
Supports power supply for up to 150 meters of Category 5 cables (traditional standard is 100 meters), and ensures stable operation of end devices (such as high-speed ball machines, 70W) through intelligent voltage drop compensation algorithms;
Built in lightning surge protection (common mode 6kV), suitable for complex outdoor electromagnetic environments, extending equipment life by more than 2 years.
4、 Purchasing Guide: How to Choose a High Compatibility PoE Switch
Clarify power requirements and redundant design
Configure the total power of the switch according to "total device power consumption x 1.2 times", for example, 10 30W devices need to choose models with a total power ≥ 360W;
Newbridge PoE switches offer multiple power specifications ranging from 150W to 2400W, supporting dual power modules (AC/DC optional) to meet N+1 redundancy backup requirements.
Certification and compatibility testing
Prioritize products certified by IEEE 802.3bt to ensure interoperability with mainstream PD devices such as Hikvision, Dahua, Cisco, etc;
Newbridge's entire range of switches have undergone rigorous compatibility testing and support plug and play without the need for additional drivers or configurations.
Management functionality and scalability
Support multiple management methods such as SNPv3, Web GUI, and CLI to achieve remote configuration, real-time power consumption monitoring, and fault diagnosis;
Built in EnergyView energy management system can generate port power consumption reports, helping enterprises optimize their electricity costs.
5、 Future Trends: Innovative Directions for PoE Technology
Higher power and farther transmission
The next generation PoE standard (such as IEEE P802.3bz) plans to increase single port power supply to over 250W and support fiber optic transmission, meeting the needs of ultra-high power consumption devices such as 5G macro base stations and autonomous driving computing platforms. Newbridge has initiated related technology research and development, and is expected to launch the first 250W PoE switch in 2026.
AI driven intelligent power supply
Combining machine learning algorithms, Newbridge is developing an AI Power intelligent power supply system that can predict peak device power consumption, identify abnormal power consumption behavior, and automatically adjust power supply strategies to help enterprises achieve energy savings of over 30%.
Integration of Green Energy and PoE
For off grid scenarios, Newbridge plans to launch PoE switches that support solar and wind energy input, achieving a hybrid power supply of "renewable energy+PoE" through energy storage modules, suitable for fields such as smart agriculture and field monitoring.
Newbridge PoE Switch - The Industry's First Choice for Full Standard Compatibility
In today's era of diversified smart devices and differentiated power requirements, the compatibility of PoE switches has become a core consideration for network deployment. Newbridge, with a deep understanding and technological innovation of the IEEE 802.3af/at/bt standard, provides global users with "high compatibility, high reliability, and high intelligence" power supply solutions. From basic office to industrial applications, from low-power sensors to hundred watt level devices, Newbridge has always driven industry progress with technological leadership. Visit www.cnnewbridge.com now to explore how Newbridge PoE product line empowers your network infrastructure!