As connected devices proliferate in the Internet of Things (IoT), companies need an efficient over-the-air (OTA) update mechanism for remotely delivering new software, features, firmware updates and security enhancements to potentially huge numbers of geographically dispersed embedded devices.
Pushing software updates can range from a few to hundreds of megabytes. Consideration needs to be given to the amount and frequency of data that will be transmitted from the device to the cloud for both cost and latency reasons. To reduce the amount of data needing to be transferred during updates, snaps supports a form of data compression known as snap deltas.
Snap deltas constitute a form of differential data compression where the only data transmitted is that which changed between the snap currently on the device and the new version. When the publisher of a snap (in the case of devices, usually the device manufacturer) releases a new revision of their snap, the Snap Store servers look at the most likely revisions that devices in the field may need meaning only the delta change is updated rather than the entire application.
Rigado, a global provider of commercial IoT edge-as-a-service solutions including a containerised application platform, are taking advantage of this technology on their gateways. Using snap deltas, the monthly bandwidth consumption for Rigado devices is reduced by up to 65 percent. Similarly, Dell’s Edge Gateways, which enable analytics at the edge of IoT networks, use snap delta to reduce bandwidth consumption by 60.5 percent.
As these examples show, the use of snap deltas can deliver significant savings in bandwidth when deployed across thousands of IoT devices. As the IoT grows and these devices reach the millions, the positive impact becomes even more substantial.
To learn more about snap deltas, how they can