SMS has lost its cool and it's been replaced by apps like WhatsApp, Signal, Threema. This is why many people miss the fact that SMS messages can play a pivotal role in remote IoT device management and automation. What makes it different? SMS works without a data connection, making it a reliable way to communicate with a remote IoT device. This makes it a powerful tool used to improve the deployment and automation of IoT devices. Here are three ways SMS makes a difference:
1. Configuring connectivity with SMS
Remote IoT devices leverage long range wireless networks, just like your mobile phone does. Unlike your phone, however, they often need some additional configuration to function properly with a network operator. While it's possible to have a device pre-configured during production, moving the configuration to the end of the sales pipeline makes it customizable, which in turn makes it future-proof.
One painful scenario for companies managing thousands of remote devices is a change in wireless provider. Not only do they need to swap out countless SIM cards, they need to configure each device to function with the new provider. By building the devices to accept SMS parameters, companies make it easier to both set the initial connectivity configuration, and to change that configuration at a later date.
2. Save the Battery with SMS
Mobile data usage is a battery killer. Maintaining an active connection sucks that battery dry, which is why many IoT device manufacturers reduce the number of times a device makes a data connection. This can be further reduced, or even removed by leveraging SMS.
One great use case for this type of system would be your average asset tracker. Asset trackers function by sending the coordinates of the device to a server on a regular basis. Leveraging SMS for data transmission removes the need for the mobile data connection, which in turn saves the device's battery.
Then comes the question: should I remove the device's ability to connect with a mobile data network? The answer: No!
A mobile data connection is useful when performing updates, or retrieving additional information from a device that may not fit in a standard SMS.
3. Use SMS to trigger a device to do any programmed task
With SMS in place for your remote configuration, you can also use it to trigger additional actions on a device. For example, if you wanted to perform an update, you could use SMS to trigger a firmware OTA update.
How about a device reboot?
When managing a remote device that dropped its mobile data connection, a quick reboot could trigger it to reestablish that connection. You’ll want to build in a mechanism to do this without relying on that missing data connection.
What are you doing with SMS?
Are you using SMS differently than I described here? Let's talk about it! You can reach out to me on Twitter, or by sending me an email.
Jeff is a super nerd with four years of experience in IoT including three years in blockchain. He’s worked as a door-to-door salesman, research assistant, developer and more. Currently he is a Lead Product Manager at EMnify.
Frequently Asked Questions
Why is SMS important to IoT devices?
SMS can be used without establishing a mobile data connection, and can be queued in the event that the device isn’t able to receive the message at the moment it was sent. This allows it to be used in situations when mobile data is unavailable, unreliable, or not necessary. For example, data can be transmitted via SMS, or SMS can trigger the device to perform an action, such as a reboot.
How do I use SMS for my IoT devices?
You’ll need to build the functionality into the device itself usingstandardized AT Commands. We created a video walkthrough on how to send an SMS to an IoT device using EMnify, and you can find thathere.
Is there a point when SMS shouldn’t be used for an IoT device?
SMS is an additional tool, and not the catch-all. If you need to send a lot of data, or maintain a live connection with a device, then SMS shouldn’t be used for that. However, there are still functions such as triggering a device reboot, or configuring the device APN that can be added to almost any IoT device. Just keep in mind that SMS may have a larger price per message than sending data over the mobile network.