Subscription Containers: Smart Multi-IMSI for IoT
Written by: Ken Otsuki
Published: July 22, 2020
Better coverage in more places
For the past 15 years, I’ve been working in a very specialized corner of the telecom world: SIM card development. Like IoT, it’s an area that pulls from a lot of different disciples: software, hardware, design, materials science… and as in IoT, no one can really do it alone. Every SIM card represents a set business partnerships and commitments that spans the globe.
Today I’m happy to be able to share more about the work we’ve been doing behind the scenes in recent months to make the Soracom IoT SIM card an even better tool for IoT development. In particular, I’m happy to announce:
- Expanded global coverage
- A new Subscription Container function that gives multi-IMSI capability to both eUICC and standard UICC SIM cards
Expanded global coverage
Outside of Japan, most Soracom SIM cards and eSIMs use what we call “Plan01s,” which now provides access to service in 145 countries on up to 285 different carrier networks. In the map below, if your region is identified in blue, Soracom plan01s will connect your devices! And wherever you connect, you get built-in access to the Soracom user console for network management, plus advanced features like SMS, USSD, serverless data storage and visualization (Soracom Harvest), on-demand remote access (Soracom Krypton), on-the-fly data translation (Soracom Orbit) and much more.
For a complete, always-updated list of supported regions and carriers, see the Soracom Developer Site: https://developers.soracom.io/en/docs/reference/carriers/
Introducing Subscription Containers
The Soracom IoT SIM is used all over the world, but data rates can vary depending on country and region. In certain areas, data may be expensive, or may not be available on your preferred carrier network of your choice.. Especially for devices in Japan and Asia, data costs can vary significantly, and will usually run high compared to the specialized plans that we can offer in Japan.
While it’s not a show-stopper, this can present some challenges to large-scale deployment in Asia. Naturally, we’ve been looking for ways to remove these barriers and help our customers scale. We’re happy to be able to announce a solution: Soracom Subscription Containers, offering advanced multi-IMSI capability for Soracom SIM cards and eSIMs.
What is a subscription container?
Most engineers, and especially cloud engineers, are already familiar with the concept of software containers like Docker. And all of us are familiar with the container concept, where for example many different things may be packed into a physical container for shipping.
In this case, our containers can hold multiple data subscriptions. Typically, a SIM card maintains a single data subscription, representing an IMSI (subscriber identification information), an MSISDN (phone number), and a set of permissions allowing connection to a specific mobile network in a specific region or country as shown below.
Because the Soracom IoT SIM comes with a dedicated SIM applet already implemented, users can now add multiple subscriptions through the applet’s internal subscription container engine. Managing and switching between subscriptions is handled as needed through the Soracom User Console or API.
So with Subscription Containers activated, the picture now looks like like this:
As of today, we are pleased to announce two new plans for this feature that make it easier to scale deployments in Japan and across the Asia-Pacific region.
- Plan X1: A plan that can be connected to KDDI LTE lines in Japan, and is compatible with the existing plan 01s ($0.2/MB for NTT DOCOMO network) for $0.02/MB
- PlanP1: SoftBank 3G/LTE lines in Japan plus APAC-specific plan supporting 2G/3G/4G (LTE) available in 20 countries. Available in APAC regions from $0.02/MB
- Orange: planX1/P1 available
- Green: planP1 available
- For up-to-date information on countries, carriers, and pricing, please visit the developer page for Subscription Containers
One nice feature in the subscription container is that your devices can automatically select the best fit for each country from among the multiple subscriptions stored in the system. And of course you always have the option to choose the best plan manually to ensure that you always have the best plan for your location and specific requirements.
Activating Subscription Containers
Since the Soracom Global IoT SIM already has a subscription container feature, you won’t need to replace any existing SIM cards. Just add plans as needed through the Soracom User Console or API.
Let’s take a look at how it works in the User Console. In the case below, I’ll walk through adding plans to an LTE device that I would like to connect to both KDDI and NTT DoCoMo networks as shown in the diagram below:
- Login to the user console and go to Global Coverage.
- Select the target line and go to “Operations” > “Add Subscription
- Select the subscription type you want to add on this screen. In this case, select I’ll planX1 and press “Add”. Over-the-air (OTA) delivery of the specified subscription will begin immediately.
- After the delivery and completion of the specified subscriptions from the Soracom OTA server, the status will change from “Shipped” (OTA delivery started) to “Ready” (delivery completed) and wait for a network connection from the device*
- When the actual connection to the network is completed, the status will change to “Active” just like a conventional SIM Transition**
After pressing the Add button, you will see the IMSI associated with the target line (SIM ID) The status of planX1 changed from one to two and planX1’s status became Shipped. After a few more seconds, the status of planX1 became Ready. This completes the OTA distribution!
In the session history, I can see that the plan switchover is complete and my device is connected to the KDDI network on planX1. That’s all you have to do to make sure that the subscription delivery -> plan switch -> network connection is complete.
*Delivery completion time depends on the network environment and performance of your device.
**After adding a subscription, the connection time to another network using the new plan depends on your device’s performance and implementation. If you are set to “Ready” and still cannot connect to the network, you may need to reboot the device. Please try to manually select a supported carrier.
