Cellular connectivity remains one of the most popular IoT connectivity solutions at the moment, especially for large-scale IoT deployments that span different countries. Cellular connectivity, along with satellite, remains the two only viable options capable of international or even global coverage.
However, as a large-scale connectivity solution, cellular connectivity is not (yet) perfect, and one of the most prominent issues with it is how the traditional SIM cards are typically tied to a single network provider: when an IoT device is moved to another country and must connect to another network, we’ll need to physically replace the SIM card. Logistically, this can be a major issue.
This is where the eSIM technology comes in as a viable solution in cellular IoT deployments.
What Is an eSIM?
eSIM stands for “embedded SIM”, referring to the newest form factor of the SIM, where instead of being a plastic card, the SIM chip is now embedded or soldered on the device.
SIM, or Subscriber Identity Module, is a chip that enables network providers to identify the subscriber’s identity, the plan he/she subscribed to, and provide the respective service according to the information included in the SIM. Traditionally, the SIM comes in the form of a plastic card with a chip on it, but the eSIM allows a new physical form that can be soldered into the device.
The term eSIM is often used interchangeably with eUICC (embedded Universal Integrated Circuit Card), although there is a core difference between the two. The eSIM refers to the hardware component of the SIM, while eUICC refers to the software component that allows remote SIM provisioning, which we will discuss below.
Remote SIM Provisioning in IoT eSIM
Remote SIM Provisioning, or RSP, refers to the feature of the eSIM/eUICC that allows the eSIM to be able to download and store multiple identification data from different network providers. “Provisioning” here refers to the process of attaching certificates and profiles to a SIM, so RSP simply means that we can provision the SIM remotely without touching the physical SIM card.
In practice, this allows us to use a single eSIM to access multiple data plans from different network providers in a single device, and the impact in IoT implementations is tremendous. Typically we can simply use an app to send over-the-air commands to the eSIM to easily switch between networks.
For example, when we’d like to switch to a new data plan for a remotely-deployed IoT sensor, we don’t need to replace the SIM card, which can be a major logistic issue. Also, for mobile IoT devices that move between different cellular coverage areas, like autonomous vehicles, RSP can allow the device to seamlessly switch between networks with minimal lag time.
eSIM Use Cases in IoT Deployments
As discussed, the most important benefit of the SIM card is that it’s possible to manage, download, and remove network profiles remotely. This allows us to change the mobile network operator without having to touch the device and replace the SIM cards, ensuring the IoT devices can stay in operation at all times.
There are three typical use cases of eSIM in IoT implementations:
Use Case 1: Consolidating Your IoT Connectivity Providers
With eSIM and RSP, businesses that are looking to scale their IoT deployment internationally or even globally can achieve global IoT connectivity with just a single provider instead of multiple local/regional providers.
By partnering with IoT eSIM providers, we can gain several benefits in our IoT deployments, including:
- Lower overall cost compared to subscribing to multiple local providers which will translate to multiple SIM cards per device
- Improved reliability and lower latency
- Network access in countries where permanent roaming is prohibited (like China and Brazil)
Use Case 2: Using Multiple Service Providers To Maximize
Another typical use case is to use two or more service providers with a single eSIM. This is common when an IoT device has been manufactured in one location but deployed in many different countries.
The main benefit in this use case is the streamlined logistics compared to using multiple local SIM cards, while we’ll still get the flexibility of using multiple local service providers to allow better reliability and cost-efficiency.
However, keep in mind that at the moment, service providers that support eSIM/eUICC for IoT are still pretty limited, and the mobile operator needs to have advanced technology to manage the location of the SIM card unless this is purchased as a service from the network provider.
Use Case 3: Switching To a New Service Provider
Another typical use is to easily switch the SIM profile remotely over the air rather than switching the SIM card. This will eliminate various logistic issues and ensure we are using the most optimal network provider in any situation.
However, keep in mind that there is still a cost attached to switching providers, and it might not be cost-effective to use this option in IoT deployments where physically replacing the SIM card isn’t a major issue, for example in smaller IoT projects where we can easily access the SIM cards (i.e. smart home).
Conclusion
eSIM can be a viable solution for various IoT deployments use cases that utilize cellular connectivity. Remote SIM Provisioning of the eSIM allows IoT devices to seamlessly switch between different operators and data plans without needing to physically replace the SIM card.
