Announcing the Twilio Super SIM

October 18, 2018
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Today Twilio is excited to announce the Twilio Super SIM, the only SIM you will ever need.

Over the last two years, we've worked with our customers to better understand their connectivity needs as they build and deploy IoT devices around the world. We've jotted down notes, collated requests and arrived at three core requirements. Our customers told us that they wanted a single SIM with a single API that they could deploy anywhere. They wanted a SIM that has access to the largest range of networks possible with smart network selection and the ability to override automatic network selection if required. Finally, they want detailed visibility into how their devices are initializing and maintaining connections to the network for debugging. With these requirements in mind, we set out to build the Super SIM.

What Makes Twilio Super SIM “Super”?

The Twilio Super SIM takes advantage of the Super Network, an operator abstraction layer managed by Twilio. We have partnered with best in class carrier families Three Group, Singtel and Telefonica to deliver connectivity our developers can trust. These families each have a strong regional focus in addition to a complete global footprint. The Super SIM has access to the superset of all networks these operators can access. The reach of the Super SIM is not static and can be improved as market conditions or customer requirements evolve. Twilio can add new operators or negotiate new rates and all Super SIMs will transparently benefit from these improvements. We take on the work of optimizing our network for cost and coverage to ensure that you, our customers, get the benefit of multiple providers with the simplicity of a single billing relationship and a single API.

Getting close to the metal

To take advantage of multiple providers, you need a SIM that's smarter than your average SIM. We looked at a number of solutions to expose the capabilities of the Super Network on a SIM and settled on designing a SIM with a Multi IMSI applet. This applet allows the SIM to decide on the provider to use for any given location or network. The modem communicates its location to the SIM and the SIM has a table of operators for a given geography and their relative priorities, the SIM can then select the preferred operator. Designing a SIM helped us better understand what is possible within the existing specifications and how we might continue to iterate on the Super SIM. The Twilio over the update platform enables this iteration. It's tricky to design a SIM but even harder to design one that will remain optimally configured for years at a time. Therefore it was essential for us to have a way to keep out SIMs in sync with the best available operator configuration. This is solved by our OTA platform, which pushes new configurations to our SIMs as they come online, ensuring they’re up to date. Our SIM and OTA platform are the foundation that allows us to build up the rest of the Super SIM stack.

To the Core

The largest piece of infrastructure for the Super SIM is the Twilio’s mobile core infrastructure. It is a pure software 2G, 3G and LTE mobile core deployed in AWS. Bringing the mobile core under Twilio's control enables a range of Super SIM features like regionalized internet breakouts and flexible network steering. The passive benefits of owning our own mobile core are all the things that developers have come to expect from cloud deployed services: global scale, high availability and fast iteration cycles. The direct benefits of running a mobile core are that we can provide extremely granular debugging information as we have a complete view of the signaling and data channel. We're excited by the capabilities that we gain from continuous improvement on our own mobile core and the platform it provides for building new features as we learn more about what developers need.

Stacking it all up

Layering together the Super Network, SIM, OTA platform, and mobile core provides the stack for the Super SIM and allows us to execute on our vision of one SIM with one API with global reach. We think the combination of excellent coverage, granular network access controls, and detailed debugging information make the Super SIM the last you'll ever need. The Super SIM is currently in a limited pilot stage while we gather feedback and harden the systems. We look forward to onboarding customers to a public beta in the first half of 2019. We can't wait to see what you build with the Twilio Super SIM!