The low power wide area networks (LPWANs) that have been emerging to support smart city and IoT services are in a fragmented state. The market recently seemed to be consolidating around two cellular options (NB-IoT and LTE-M) and two main unlicensed ones (LoRA and Sigfox), though some specialist choices like Wi-SUN are gaining ground too.
But now Amazon threatens to throw a cat among the pigeons with the launch of Sidewalk, a LPWAN protocol to connect sensors over very wide areas, in the unlicensed 868/900 MHz spectrum (where most unlicensed LPWANs also operate). Amazon claims it will differentiate its technology from more established alternatives with its level of security, particularly when it comes to over-the-air updates, harnessing some of the encryption and message distribution systems it has in use for its retail and cloud services platforms.
This is the latest example of Amazon investing in the wireless connectivity which will increasingly link its central or edge clouds to end users and sensors. While the company has close ties to many telcos, its work with CBRS shared spectrum applications – and other non-MNO connectivity options – reflects its belief that operators will not control wireless networking in all scenarios. In some enterprise, city and industrial environments, it will be essential to encourage a diversity of connectivity providers if Amazon and AWS are to be able to reach every type of user and object.
The company said it had developed Sidewalk as a middle path between WiFi, which still has range constraints despite the standardization of its long range version, HaLow; and 5G, with its relatively high power and complexity. “That leaves a middle ground for devices that are looking for low cost, low power, low bandwidth connection where battery life needs to be measured in years, not days,” said Dave Limp, SVP of devices for Amazon.
The next stage will be to drive the evolution of a full ecosystem around Sidewalk, something Amazon is uniquely expert in doing, as seen in its developer platforms and tools for retailers, Greengrass edge/IoT services, cloud applications, and content platforms. Limp expects developers to build “all kinds of useful, low cost products” for the Sidewalk network, giving the examples of garden weather stations, water sensors and connected mail boxes. The company will accelerate progress towards a huge base of devices and applications by developing reference designs for certain mass market products (the first being a dog tracker).
Amazon is initially testing its protocol in Los Angeles, having sent Sidewalk-enabled devices to 700 employees of its Ring subsidiary. Limp said it was able to cover the LA Basin area within a few weeks, and using only “a few access points”.