Posted On: Jul 9, 2020
AWS IoT Core is announcing a new feature called named shadow, which allows you to create multiple shadows for a single IoT device. A device's shadow is a JSON document that is used to store and retrieve state information for a device.
IoT devices often have multiple state data such as user settings, manufacturer configuration, and operational status. Each of these state data needs to be accessed by different users or at differing frequencies. Until today, you can only associate one shadow to a device and are required to store all sets of state data in one shadow. As a result, all users must have access to the entire shadow and can consequently read and update state data they shouldn’t. In addition, devices with large state data set may quickly run into the shadow size limit. Now, you can store different device state data into different shadows, and as a result access only the required state data when needed and reduce individual shadow size.