Currently, only the T-Mobile NB-IoT network in the United States is supported.
Twilio's Narrowband SIM is presented in partnership with T-Mobile US and enables access to the T-Mobile Narrowband (NB-IoT) network.
Narrowband technology enables high volume, low bandwidth, and data-only Internet of Things (IoT) use cases. These 'Massive IoT' applications involve huge numbers of low-complexity devices that send or receive messages infrequently. Typical use cases include low-cost sensors, preventative maintenance monitors, utilities meters, and location trackers. Devices like these are often deployed in challenging radio conditions, such as in building basements or outdoors at the extremes of network tower coverage. They often rely solely on battery power and may need to stay operational for years between maintenance checks.
Narrowband was designed specifically to improve the power consumption of devices that send small or infrequent packets of data. Its technical fundamentals reduce the cost of connectivity and lower the cost of hardware.
Narrowband SIM is a data-only service.
In order to connect to the T-Mobile Narrowband IoT network, a commercial IoT device must be pre-certified by T-Mobile US. The easiest and quickest way to achieve certification is to base your device on an already certified cellular module, such as the Quectel BC66 NB-IoT modem.
You can check if your chosen module is permitted by T-Mobile by looking it up in this list of certified modules.
To learn more about certification requirements for your Narrowband device, please see Device Certification for Production .
Twilio's Narrowband SIM operates much like the Programmable Wireless SIM — you use the Programmable Wireless API to manage Narrowband SIMs, for example — but there are a number of small differences that you should be aware of if you have used other Twilio IoT SIMs before.
You can order Narrowband SIMs from the Console. You can order a three-SIM Starter Pack or bulk-order Narrowband SIMs (minimum order size ten SIMs). Starter Pack SIMs need to be registered with your Twilio account through the Console. Bulk-ordered SIMs will be linked to your account automatically.
Narrowband SIMs use the same set of SIM states and Sim resource status values that are used by Programmable Wireless SIMs.
To learn more about Narrowband SIM states, please see this page.
Narrowband SIM usage limits are managed using Rate Plans. Because these SIMs only operate in the US, and for data only, not all of the Rate Plan options you may be familiar with from working with Programmable Wireless SIMs are available to Narrowband SIMs.
To learn how Rate and Data Metering Plans work for Narrowband SIMs, and to find out how to create and apply Plans, please see this page.
A Narrowband SIM is ready to use after it has been assigned to a Rate Plan and it has been activated.
Twilio provides a free SDK, called Breakout, to abstract away some of the more complex elements of narrowband-based Massive IoT deployment, such as cellular modem hardware and cellular network registration. The Breakout SDK allows developers to exchange data between low-powered narrowband devices and their cloud-based services.
To learn how to incorporate the Breakout SDK into your IoT application, please see this tutorial.
Narrowband incorporates a number of technical innovations to reduce device power consumption. If you'd like to learn more about these Narrowband features and how they might enhance the operation of your IoT product, please see this guide.