What is Reverse PoE Switch

A reverse PoE (Power over Ethernet) switch is a type of network switch that can supply power to network devices (such as IP cameras, wireless access points, or VoIP phones) through Ethernet cables, but with a twist: it receives power from the connected devices rather than providing it.

Typically, PoE switches deliver power to devices via Ethernet cables, which is the common PoE standard (IEEE 802.3af/at/bt). However, in a reverse PoE setup, the roles are flipped:

• The switch receives power from a connected PoE-enabled device.
• The device can be powered by an external source, and it will supply power back through the Ethernet cable to the switch.

This is often used in situations where you want to centralize power management or reduce the need for separate power adapters. Reverse PoE can help with managing power from remote locations or devices that are designed to supply power back to the switch. However, reverse PoE is less common in typical networking environments compared to standard PoE.
In the reverse PoE setup, the connected PoE device (like a powered camera or a router) provides power to the switch. This configuration is much less common than traditional PoE because switches usually supply power rather than receive it. However, reverse PoE can be used in certain situations, like when the switch is in a remote location and needs to be powered by the device it’s connected to, or for specific energy-saving or power-sharing setups.

Use Cases

• Redundant power: If a device connected to a reverse PoE switch has an external power source, it can act as a backup for powering the switch itself.
• Energy-efficient designs: In some environments, reverse PoE might be used for energy optimization, especially where equipment is designed to harvest power from other devices.

Reverse PoE (Power over Ethernet) switches are specialized devices with niche applications.

They are particularly useful in scenarios where providing a dedicated power source for the switch itself is challenging or impractical. Below are some common applications of reverse PoE switches:

1. Remote Network Deployment

Scenario: In remote or rural areas where conventional power outlets are unavailable or limited, reverse PoE switches can be powered by devices like wireless routers or access points.

Example: Setting up internet access points in remote locations where power is only available at the edge device (e.g., a router powered by solar energy or batteries).

2. FTTH (Fiber to the Home) Networks

Reverse PoE switches are widely used in Fiber to the Home deployments.

Scenario: In multi-dwelling units or apartment buildings, the optical network terminal (ONT) or customer premises equipment (CPE) devices at each user's home can supply power back to the reverse PoE switch via Ethernet.

Benefit: Reduces the need for centralized power at the switch and simplifies wiring.

3. Energy-Efficient Networks

Reverse PoE setups can be part of energy-efficient designs.

Scenario: Devices with their own power sources can supply energy to switches, reducing the need for additional energy infrastructure.

4. Cost-Effective Power Sharing

In budget-conscious environments, reverse PoE allows connected devices to share their power, eliminating the need for individual power supplies for the switch.

Example: Small office or home networks where power sources are sparse but devices like PoE routers or adapters can act as a source.

5. IoT and Smart City Applications

Reverse PoE switches can be used in IoT networks where devices are distributed across large areas.

Example: Outdoor surveillance cameras or smart sensors supply power to switches in locations like parks, campuses, or smart city installations.

6. Temporary Network Setups

Scenario: Reverse PoE is useful in temporary setups like exhibitions, outdoor events, or emergency situations where