In preview since re:Invent, AWS IoT ExpressLink is a service introduced to create secure IoT devices, hiding the complexity of implementing cloud connectivity, a process that usually requires multiple steps like connecting to a physical layer, establishing TCP/IP communication and logging into an MQTT broker.
Espressif, Infineon Technologies, and u-blox are the AWS partners that have developed wireless modules that support multiple connectivity options, including wi-fi and cellular. Channy Yun, principal developer advocate at AWS, uses an example of a pool pump to explain the benefits of the new service:
Some devices are too resource-constrained to support cloud connectivity, meaning their processors are too small or slow to handle the additional code. For example, a small piece of equipment, like a pool pump, may contain a tiny processor that is optimized to drive a particular type of motor but does not have the memory space or the performance necessary to handle both the motor and a cloud connection. (…) You can keep the tiny processor in the equipment, and delegate the heavy lifting of connecting to the cloud to AWS IoT ExpressLink, allowing the manufacturer to make the simple application software, and avoid costly redesign.
According to AWS, the service is compatible with devices of all sizes and resource constraints, making it possible to retain existing processors. IoT ExpressLink integrates with other AWS IoT services, such as AWS IoT Jobs and IoT over-the-air (OTA), to schedule and perform updates, and AWS IoT Device Management, to monitor and update fleets at scale.
The modules implement best practices for device-to-cloud connectivity, creating cryptographically signed certificate with unique device ID, supporting cryptographically secure boot,TLS v1.2 or higher encryption of wireless connections, cryptographically secured OTA firmware updates, and encryption of all sensitive data stored on the module.
A repository with IoT ExpressLink examples is available on GitHub. Customers can order evaluation kits and send telemetry data to the cloud through the serial interface. The price of a module with IoT ExpressLink depends on the features and hardware manufacturer, starting at around 26 USD. AWS does not charge additional fees for using the service.