A switch is a network device that operates at the Data Link Layer (Layer 2) of the OSI model, primarily used to forward data frames between devices within a Local Area Network (LAN). Unlike routers, switches focus on data exchange within the LAN, utilizing a MAC address table to accurately send data packets to the intended device, thereby preventing broadcast storms and enhancing network efficiency.
The working principle of a switch can be summarized simply as “learning, forwarding, filtering.” When a device sends data, the switch records the MAC address of the sender and forwards the data to the correct port based on the destination MAC address. If the destination address is not in the MAC address table, the switch broadcasts the data to all ports (except the sending port) until it finds the target device.
Both Non-PoE Switches and PoE switches are based on this core principle, but PoE switches add power supply capabilities on top of the basic switching function, giving them an advantage in certain scenarios.
1. Introduction of Non-PoE Switch
A Non-PoE Switch is the most basic type of switch, primarily responsible for forwarding network data. It connects various devices (such as computers, printers, servers, etc.) through Ethernet ports and efficiently transmits data based on MAC addresses.
The core functions of a Non-PoE Switch include:
· Data Forwarding: forwarding data packets from one port to another based on the MAC address table.
· VLAN Support: isolating network traffic through Virtual Local Area Network (VLAN) technology to improve security and management efficiency.
· Bandwidth Management: supporting ports with different rates (10/100/1000Mbps or even 10Gbps) to meet the needs of various devices.
· Management Functions: some advanced Non-PoE Switches support management features, such as port mirroring, traffic monitoring, and Quality of Service (QoS) control.
Non-PoE Switches are divided into unmanaged and managed types. Unmanaged switches are plug-and-play, suitable for small network environments like homes or small offices; managed switches offer more detailed configuration options, suitable for enterprise or complex network environments.
2. Advantages of Non-PoE Switch
Low Cost: Non-PoE Switches are relatively inexpensive, especially unmanaged switches, making them suitable for scenarios with limited budgets.
Easy Deployment: No complex configuration is required, facilitating rapid network setup.
Versatility: Applicable to most network environments, from home to enterprise use.
High Performance: Supports high-speed data transmission, meeting the bandwidth demands of modern networks.
3. Limitations of Non-PoE Switch
The primary limitation of a Non-PoE Switch lies in its single function, offering only data forwarding capabilities and unable to supply power to devices. In scenarios where network devices such as IP cameras or wireless access points need power supply, a Non-PoE Switch must be used in conjunction with additional power adapters or power supply equipment, which increases wiring complexity and costs. Moreover, in certain specialized scenarios, additional management features might be needed; without these, it may be challenging to meet complex network requirements.
4. Introduction of PoE Switch
A PoE Switch is a device that has integrated Ethernet Power Supply (PoE) technology based on a standard Non-PoE Switch. It transmits data and power simultaneously over standard Ethernet cables (such as Cat5e or Cat6) to power devices that support the PoE protocol, such as IP phones, surveillance cameras, and wireless access points. The core of PoE technology lies in utilizing idle wire pairs or data wire pairs within the Ethernet cable to transmit direct current, eliminating the need for additional power cords.
The working principle of a PoE Switch is based on standards such as IEEE 802.3af, 802.3at, and 802.3bt:
· IEEE 802.3af: provides a maximum of 15.4W of power, suitable for low-power devices like IP phones.
· IEEE 802.3at (PoE+): delivers up to 30W of power, suitable for medium-power devices such as high-definition cameras or wireless access points.
· IEEE 802.3bt (PoE++): supports higher power levels (up to 90W), suitable for high-power devices like LED lighting or PTZ cameras.
When supplying power, a PoE Switch first detects whether the powered device (PD) supports the PoE protocol through the Power Sourcing Equipment (PSE), ensuring safe power delivery. Only when compatible devices are detected will the switch transmit power through the Ethernet cable, preventing damage to non-PoE devices.
Baudcom's 8-port PoE Switch (Model: BD-S1010FSP) exemplifies this technology with 8×10/100M PoE ports supporting IEEE 802.3af/at standards, delivering up to 30W per port with a total PoE budget of 120W. The switch also features 2×10/100M uplink RJ45 ports for flexible network connectivity.
5. Advantages of PoE Switch
· Simplified Wiring: Transmits data and power simultaneously through a single Ethernet cable, eliminating the need for additional power cords and reducing wiring costs and complexity.
· Flexible Deployment: PoE Switches can be installed in areas without power outlets, such as ceilings or outdoor locations, making them suitable for surveillance and wireless network scenarios.
· Centralized Management: PoE Switches typically support remote power management, allowing software control of power switches for devices, which improves maintenance efficiency.
· High Security: PoE Switches feature built-in overload protection and short-circuit protection mechanisms to ensure safe power supply.
6. Limitations of PoE Switch
Although PoE Switches are powerful, they also have some limitations:
· Higher Cost: The price of PoE Switches is usually higher than Non-PoE Switches, especially for models supporting high-power standards.
· Power Consumption Limits: The power supplied to each port is limited by PoE standards, and some high-power devices may require dedicated power sources.
· Compatibility Issues: Not all devices support the PoE protocol; Non-PoE devices require additional PoE splitters or adapters.
· Heat Dissipation Needs: PoE Switches generate more heat during power delivery and require good heat dissipation designs or fan support.
7. Comparison between Non-PoE Switch and PoE Switch
In order to understand the differences between the two more intuitively, the following will compare them from multiple dimensions:
|
Characteristics |
Non-PoE Switch |
PoE Switch |
|
Function |
Data transmission only |
Data transmission + power supply |
|
Cost |
Lower |
Higher |
|
Wiring Complexity |
Requires additional power cable |
Just one Ethernet cable |
|
Application Scenarios |
General network environment |
Surveillance, wireless AP, IP phones, and other scenarios requiring power supply |
|
Power Support |
None |
Supports 15.4W to 90W (depending on standards) |
|
Deployment Flexibility |
Limited by power outlet location |
Can be deployed in areas without power sources |
|
Management Features |
Both unmanaged and managed types |
Usually managed, supports power management |
8. Application Scenarios
Non-PoE Switch
Non-PoE Switches are widely used in network environments that do not require power supply:
· Home Network: Connect computers, smart TVs, gaming consoles, and other devices to meet daily internet access needs.
· Small Office: Provide network connections for employee computers, printers, and servers, supporting small LANs.
· Data Center: In server clusters, Non-PoE Switches are used for high-speed data transmission, usually as managed switches.
For example, in a home network, an 8-port gigabit Non-PoE unmanaged switch can easily connect a router, NAS storage devices, and multiple computers, satisfying high-definition video streaming and file sharing requirements.
PoE Switch
PoE Switches are mainly used in scenarios where data and power need to be transmitted simultaneously:
· Video Surveillance System: PoE Switches supply power and transmit video data to IP cameras, suitable for malls, campuses, factories, and other places.
· Wireless Network Coverage: Power wireless access points (APs), supporting large-scale Wi-Fi coverage in enterprises or public places.
· VoIP Phone System: Provide power and network connection for IP phones, simplifying enterprise communication network deployment.
· Smart Buildings: Power smart lighting, sensors, and other IoT devices, promoting smart city development.
Taking a small to medium-sized enterprise surveillance system as an example, an 8-port PoE Switch can connect multiple high-definition IP cameras. Each camera can transmit data and be powered through a single Ethernet cable, eliminating the need for complicated power wiring, and supporting remote management for easy maintenance.
9. How to choose the right switch?
When selecting between a Non-PoE Switch and a PoE Switch, it is necessary to consider the following factors:
Demand Analysis:
· If only data transmission is needed, and devices have independent power supplies, a Non-PoE Switch is a more economical choice.
· If power supply for devices is required (such as surveillance cameras, wireless APs), a PoE Switch is a better option.
Number of Ports and Speed:
· Choose the appropriate number of ports (such as 8, 16, 24) based on the number of devices to connect.
· Ensure that the supported speed (Fast Ethernet, Gigabit, 10-Gigabit) meets the bandwidth requirements.
Power Budget:
· For PoE Switches, confirm whether the total power budget and per-port power meet the needs of powered devices. For example, an 8-port PoE Switch with a total power budget of 120W and a maximum of 30W per port can power four 30W devices simultaneously.
Management Functionality:
· Small networks can choose unmanaged switches, which are simple and easy to use.
· For enterprise or complex networks, it is recommended to choose managed switches that support VLAN, QoS, and remote management.
Baudcom's PoE switch offers reliable performance with built-in lightning protection (4KV), galvanized steel casing, and fanless design for quiet operation, making it an excellent choice for cost-effective PoE deployments.