In an effort to improve security of IoT devices, Microsoft announced Azure Sphere, an end-to-end solution for Internet-connected microcontrollers (MCUs), during the April 2018 RSA infosec conference. Azure Sphere is organized around a three-layer architecture composed of hybrid microcontrollers running a new IoT-optimized Linux kernel and leveraging a cloud-based security service. The first Azure Sphere chip, the MT3620, is developed by MediaTek Inc and is expected to be publicly available in the third quarter of 2018.
The new MCUs are called “crossovers” by Microsoft because they combine both real-time (Cortex-M) and application (Cortex-A) processors into an MCU package, a necessary complexity in order to run a Linux distribution which is by nature CPU and memory intensive.
