When setting up a fiber network, choosing the right type of ONU (Optical Network Unit) is very important. Two popular types are Reverse PoE ONU and PoE ONU. They both use Ethernet cables to send data and power, but they work in opposite ways. Understanding the difference between these two can help you pick the best one for your network setup.
What is a Reverse PoE ONU?
A Reverse PoE power over ethernet ONU is a special device that gets power from other equipment, like a PoE switch or router. This is called Reverse Power over Ethernet. Instead of plugging the ONU into a power outlet using a power adapter, it gets its power through the Ethernet cable.
This is very helpful in places like apartment buildings or offices where there is no easy access to power outlets for every ONU. With Reverse PoE, you only need to power the switch or router. That power then flows back through the Ethernet cable to the ONU.
In this setup:
The ONU is the PD (Powered Device) — it receives power.
The switch or router that supplies power is the PSE (Power Sourcing Equipment).
For example, Imagine you install an ONU on each floor of a building. You don’t want to run separate power cables to every floor. Instead, you use a switch on each floor that sends power through the Ethernet cable to the ONU. This makes the setup simple and neat.
Before reserve, each onu work with power adaptor; After set up for reserve Poe onu, each onu only use ethernet put in.
That means:
- Reverse PoE ONU does not need a local power adapter.
- It receives power from the user’s side (like a PoE switch).
- It is good for FTTB (Fiber to the Building) networks.
- It saves power outlets and reduces cable mess.
What is a PoE ONU?
A PoE ONU works in the opposite way. It sends power to other devices through Ethernet cables. This is called Power over Ethernet (PoE). It can power things like IP cameras, VoIP phones, or wireless access points.
This type of ONU is useful in small offices, smart homes, or surveillance systems. You connect the ONU to a power outlet using a normal ONU power adapter, and it sends both internet and power to your devices.
In this setup:
The ONU is the PSE (Power Sourcing Equipment) — it provides power.
The connected device (such as an IP camera or VoIP phone) is the PD (Powered Device) — it receives power.
Let’s say you want to install an IP camera outside your home. You can connect it to a PoE ONU inside your house using just one Ethernet cable. The cable carries both data and power, so you don’t need an extra power supply for the camera.
That means:
PoE ONU uses a power adapter to get power.
It provides power to connected devices like IP cameras.
It is useful for home and office networks.
It reduces the number of power cables for your devices.
Reverse PoE vs PoE ONU: Side-by-Side Comparison
| Feature | Reverse PoE ONU | PoE ONU |
| Power Direction | Switch/Router → ONU (reverse PoE) | ONU → IP camera/VoIP phone/Powered AP(PoE) |
| Typical Use Case | FTTB, where ONU is deployed near users | FTTH, small offices powering PoE devices |
| Requires Local Power Adapter? | No, powered via Ethernet from switch | Yes, needs an external ONU power adapter |
| Power Standard | Reverse Power over Ethernet | Power over Ethernet (PoE) |
| Device Powered | ONU is powered | IP camera, VoIP phone, or AP is powered |
| Role | Acts as PD | Acts as PSE |
Why the Confusion?
Both terms involve Power over Ethernet, but the direction changes everything:
PoE ONU: “I power other devices.”
Reverse PoE ONU: “I get powered by another device.”
Which One Should You Choose?
Choose a Reverse PoE ONU if:
- You are installing ONUs in buildings without power outlets nearby.
- You want the ONU to be powered by a PoE switch.
- You are working on a large or multi-floor building project.
Choose a PoE ONU if:
- You need to connect IP cameras, phones, or wireless access points.
- You want to power those devices through one Ethernet cable.
- You are setting up a smart home or office network.
Conclusion
Both Reverse PoE ONU and PoE ONU are smart solutions that combine data and power in one cable. They help reduce the number of wires, save space, and make installation easier.
A Reverse PoE ONU receives power from devices like PoE switches and is great for buildings with no easy access to power sockets.
A PoE ONU sends power to other devices like cameras or phones and is useful for home or small business networks.
When you understand the difference, you can choose the right type for your network project.
If you’re looking for high-quality Reverse PoE ONUs or PoE ONUs, Baudcom provides reliable and cost-effective products. Contact us today to find the best solution for your needs.
To fully understand ONU/ONT, just read this article: Optical Network Unit ONU (ONT) — Complete Guide & Knowledge Hub
