eDRX: what it is and how it works within IoT and mobile networks

eDRX (extended Discontinuous Reception) is an energy-saving feature within mobile networks that is used in IoT devices. It allows a device to remain in “sleep mode” for longer periods without constantly listening to the network.

Within IoT and connectivity, eDRX is mainly applied in technologies such as NB-IoT and LTE-M to significantly extend the battery life of devices.

Summary

eDRX is a technique that allows IoT devices to be active less frequently, thereby saving energy.

Important to remember:

• eDRX stands for extended Discontinuous Reception
• extends the sleep periods of a device
• reduces energy consumption
• applied in NB-IoT and LTE-M
• ideal for battery-powered IoT devices

What eDRX is exactly

Normally, a device regularly “listens” to the network to check if data is available. This consumes energy, even when no data is received.

With eDRX, this listening interval can be extended. The device switches itself off (or into a low-power mode) for longer periods and only becomes active at fixed moments to check for incoming data.

This significantly reduces energy consumption.

How eDRX works

eDRX works by adjusting the frequency at which a device maintains contact with the network.

In practice, this means that after sending or receiving data, a device enters sleep mode. Instead of becoming active every few seconds, this interval can be extended to minutes or even longer.

When the device “wakes up” again, it checks whether data is available and processes it. After that, it returns to sleep mode.

This process repeats continuously.

eDRX vs PSM

eDRX is often compared with PSM (Power Saving Mode), another energy-saving technique.

eDRX

The device remains periodically reachable for incoming communication, but at longer intervals.

PSM

The device is completely unreachable during sleep mode and only becomes active when it wants to send data itself.

eDRX therefore offers a balance between reachability and energy consumption.

Applications within IoT

eDRX is used in applications where devices do not need to be continuously active but must remain occasionally reachable.

Examples:

• smart meters
• asset tracking with periodic updates
• sensors in smart city applications
• industrial monitoring
• agricultural sensors

In these applications, long battery life is essential.

Advantages of eDRX

eDRX helps significantly extend the battery life of IoT devices without making the device completely unreachable.

It also offers flexibility, as the interval can be adjusted to the application. This makes it possible to balance energy consumption and reachability.

Implementation of eDRX in IoT solutions

When applying eDRX, it is important to choose the correct settings.

Configuration of intervals

The length of sleep and listening cycles must be aligned with how often communication is required.

Network support

Not all networks support eDRX in the same way, so compatibility is important.

Device configuration

Devices must support eDRX and be correctly configured via firmware or network parameters.

Balance between reachability and energy

A longer sleep period saves energy but increases latency for incoming communication.

Points of attention with eDRX

Although eDRX offers many advantages, there are also considerations.

Latency for incoming messages may increase, as the device is not continuously reachable. In addition, configuration may depend on network support.

It is also important to properly test how eDRX behaves in practice.

Why eDRX is important

Many IoT devices rely on batteries and must operate for years without maintenance. eDRX makes this possible by minimizing energy consumption.

This allows large-scale IoT deployments to be more efficient and sustainable.

Conclusion

eDRX is an energy-saving technique that allows IoT devices to be active less frequently while remaining reachable. It is widely used in NB-IoT and LTE-M to extend battery life.

For organizations working with battery-powered IoT devices, eDRX provides an effective way to optimize energy consumption and extend device lifespan.

For more information, please contact us via the telephone number +31-85-0443500 or by email at info@thingsdata.com.