AWS IoT Device Defender Client Library

AWS IoT Device Defender is a security service that allows you to audit the configuration of your devices, monitor connected devices to detect abnormal behavior, and mitigate security risks. It gives you the ability to enforce consistent security policies across your AWS IoT device fleet and respond quickly when devices are compromised.

— Description of Device Defender from AWS IoT documentation https://docs.aws.amazon.com/iot/latest/developerguide/device-defender.html

AWS IoT Device Defender lets you continuously monitor security metrics from devices for deviations from what you have defined as appropriate behavior for each device. If something doesn’t look right, AWS IoT Device Defender sends out an alert so you can take action to remediate the issue.

The AWS IoT Device Defender Client Library provides a convenience API for interacting with AWS IoT Device Defender service. This library is independent of the MQTT library. Applications can use this library to assemble and parse the Device Defender MQTT topics, then use any MQTT library to publish/subscribe to those topics. Features of this library include:

It is stateless. It does not use any global/static memory.
It depends on the standard C library only.

Memory Requirements

Memory requirements of the AWS IoT Device Defender Client Library.

Code Size of AWS IoT Device Defender (example generated with GCC for ARM Cortex-M)
File	With -O1 Optimization	With -Os Optimization
defender.c	1.1K	0.6K
Total estimates	1.1K	0.6K