FOTA Testing for IoT

Firmware Over The Air (FOTA) updates allow for the remote updating of the software or firmware on IoT devices. This is important for maintaining the security and functionality of the device, as well as for rolling out new features and improvements. This can be done over a network connection, such as WiFi or cellular, and allows the device to receive updates without the need for physical access. FOTA updates are commonly used in the IoT (Internet of Things) industry, where devices may be deployed in remote locations or difficult-to-reach areas. In this article, we will cover what FOTA is, how it is done for IoT devices, the need for testing FOTA in IoT, and how FOTA testing can be done in IoT.

A bad FOTA could break your IoT Device

FOTA updates for IoT devices typically follow a similar process. First, the device manufacturer will create and release a new firmware or software update. This update will then be sent to the device over the network, either directly or through a cloud server. The device will then download and install the update, often without any user intervention.

Several challenges must be considered when implementing FOTA updates for IoT devices, such as:

  • Ensuring that the update process is reliable and secure
  • The update must be delivered to the device successfully and without interruption
  • The update must not compromise the security of the device or the network
  • The update process must be able to handle devices with limited resources, such as low memory or processing power.

Need for testing FOTA in IoT

FOTA testing is critical for ensuring the reliability and security of the update process. It is especially important in the IoT industry, where devices may be deployed in large numbers and diverse environments. FOTA testing allows manufacturers to identify and fix issues with the update process before it is deployed in the field. It is also critical for maintaining the functionality of the device. New firmware or software updates may introduce new features or improvements, but they may also cause issues with existing functionality. FOTA testing allows manufacturers to ensure that the update does not cause any unexpected problems with the device.

How to test FOTA in IoT Devices

FOTA testing in IoT can be done in several ways. One common approach is to use a test bed. This allows manufacturers to test the update process on actual devices in a controlled environment where any issues can be easily identified and resolved.

While hardware devices may give the most accurate behavior, it would be difficult to understand the full-scale impact of your change at the same scale of a hardware test bed. For example, increasing the frequency of a periodic status update payload may not affect the backend application much at the scale of a hardware testbed, But this can have drastic consequences at the full scale of your production. Furthermore, Simulated devices allow manufacturers to test the update process without risking any real devices or data. Issues can be easily monitored, identified and resolved with a very quick turnaround.

With the IoTIFY Device simulator, creating such testing and validation scenarios becomes trivial. From Checksum validation and update sequences to changing frequencies of payloads, IoTIFY tests can capture any and all stateful behavior of your device. A few exciting things you can use IoTIFY for in this use case include:

  • Providing devices with the update URL over MQTT
  • Having the simulated devices individually download the firmware over HTTP(s)
  • Measure the latency of the endpoint
  • Validate checksum if specified
  • Reboot and go through a boot sequence
  • Report back to the server upon successful update
  • Simulate errors and breaks in this flow to see how it affects your server or device orchestration pipeline.


The infinitely customizable nature of IoTIFY allows you to hone in on your test cases as accurately as you need it. With access to NPM, you can use any additional library to add to your model. You can leverage our Metrics APIs to gain interesting perspectives into such workflows. In the second half of the video below, you can see how easy it is to add metrics or customize your Device Twin.

If you would like to discuss IoTOps and the value IoTIFY can add to your workflow, please Contact Us, and we can offer a Free Consultation for your use case. You can try the platform out yourself by signing up at