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Programmable Wireless: Narrowband IoT

Twilio and T-Mobile present Narrowband

Twilio Programmable Wireless offers a new SIM which gives access to the T-Mobile Narrowband network. Narrowband technology is designed to support Massive Internet of Things (IoT) use cases (typically low bandwidth).

On this page

Alfa Developer Kit

The Developer Board provided with the Alfa Developer Kit is based on the STM32F405RG Arduino MCU series with a Narrowband U-Blox Sara-N410 cellular module. The Alfa Developer Kit includes a set of Grove sensors – humidity, light, and ultrasonic.

Breakout SDK

Breakout SDK enables developers to exchange data between low-powered devices and their services running in the cloud.

The first build target for the Breakout SDK is the U-Blox Sara-N410 cellular module running on the Twilio Alfa Narrowband Developer Kit. It supports the U.S. T-Mobile Narrowband network.

Currently, only the T-Mobile Narrowband network in the United States is supported.

In the future, Breakout will provide expanded device support across different cellular technologies.

Breakout SDK has the following design goals:

  • Abstract the complexity of cellular modem hardware
  • Handles necessary cellular network registration

Download and install the Breakout SDK

1. View the Twilio Breakout SDK for Arduino on Github

Clone the Twilio Breakout SDK for Arduino on Github. (Contributions are, of course, encouraged.)

You can follow the getting started guide to install in a few minutes the Breakout SDK onto your Arduino IDE. Then you can start sending and receiving data from the device.

Don't forget to join the Gitter channel for help, or email help-wireless@twilio.com.

2. View the Twilio Breakout SDK Environment Setup on Github

If you need help installing the Arduino IDE and other requirements to use the Breakout SDK, take a look at IDE setup guide in the Twilio Breakout Arduino Library repository in Github.

Prototype using the Alfa Developer Kit and Breakout SDK

See the Samples section for what you can do with the Massive Breakout SDK

Narrowband services through Breakout SDK

Obtaining Narrowband SIMs

Narrowband SIM orders may be placed from the Console.

Registering SIMs

Received an Alfa Developer Kit with a Narrowband SIM?

Register the SIM to your Twilio account by following the normal Starter SIM registration process. If you need help, see I've got a Starter SIM for general instructions.

Narrowband SIM Rate Plans

Narrowband SIMs require a specific Rate Plan. A Narrowband Rate Plan is created when you register a Narrowband SIM.

During the Pilot, as the only available Narrowband pricing plan is the Developer Plan, this plan will be automatically added to your new Narrowband Rate Plan.

To create a Narrowband Rate Plan without going through the SIM registration process:

  1. Visit the Create a Rate Plan section of the Console
  2. Select Narrowband for SIM type
  3. Give the Rate Plan a unique name
  4. Continue through the Rate Plan creation process
  5. Click the Create button

Narrowband network support

Currently, the T-Mobile Narrowband network supports the following:

  • User plane IP connectivity from the device through the packet gateway across the Internet to Twilio's servers.

This is likely to change throughout the Pilot. As such, it's important to always be running the most up-to-date version of the Breakout SDK.

SIM lifecycle

Twilio Narrowband SIMs support the same set of SIM Statuses as the non-Narrowband SIMs. However, the Narrowband Developer Plan does not support the ready state, but remember, Narrowband SIMs have a specific Rate Plan. See the next section.

Billing and metering

During the Pilot, only the Narrowband Developer Plan is supported. The Developer Plan is $2 per month and includes 2MB of data per month. Overages are billed at 50¢ per MB, metered and billing in 100KB increments.

The Developer Plan is designed to support 60 connections per hour.

Production Plans (to be released) are designed to support 10 connections per hour.

Frequently Asked Questions (FAQ)

Is the Super SIM related to the Narrowband SIM?

  • Not today. Today the Super SIM is designed to support 2G, 3G and LTE.

Is Narrowband available on the same SIM we sell today?

  • No. A separate physical SIM is required for Narrowband.

How much data do I get per month during the Pilot?

  • 2MB per month.

Will my Narrowband SIM work with Programmable Voice?

  • No. Narrowband IoT (the underlying radio technology) does not support voice.

Will my Narrowband SIM work with Programmable SMS?

  • No. Narrowband is not in any way designed for communications use cases.

What type of hardware is required for a Narrowband SIM?

Can I use any Narrowband cellular module device?

  • No. Cellular modules must be certified by the T-Mobile network to be used in devices. Visit the Device Certification section for more information.

Geographically, where can I use my Alfa Developer Board?

  • T-Mobile's Narrowband network is deployed in the U.S. only.

How can I order a Narrowband SIM?

  • Narrowband SIMs are not currently available for order in Console during the Pilot. Talk to Sales.

How do I create a Rate Plan for Narrowband SIMs?

Can I use an existing Rate Plan with Narrowband SIMs?

Device certification (for production)

Any product utilizing the T-Mobile Narrowband network that is intended for commercialization will need to be certified by T-Mobile.

Since the Alfa Developer Kit uses a T-Mobile certified module (the U-Blox N410B), most of the heavy lifting for certification has already been completed for you, assuming you continue to use the same module.

As the OEM/Product Developer, you will need to provide T-Mobile with device capability information.

Certification requirements include security certification, 'Safe For Network' testing, and delta certification for PTCRB. T-Mobile will also onboard the device to their Device Management platform, which today is handled for you by the Alfa Developer Kit.

Fast path to certification:

  • Use a T-Mobile pre-certified module

Required certifications and tests:

  • Module certification completed through T-mobile
  • PTCRB of the product completed
  • Device Security (CTIA) test plan
  • Device Management verified through T-mobile
  • Safe for Network (T-Mobile)
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