What Is an eSIM Card: Guide to eSIM Usage in IoT Deployments

Most of us are familiar with SIM cards: the plastic card that slots into our smartphone, tablet, or any other devices that allow us to connect to our network providers.

SIM is actually an acronym for Subscriber Identity Module, and as the name suggests, it stores user’s identity information, allowing network providers to identify a user, the data plan he/she is subscribed to, and provide service accordingly.

Nowadays, however, SIM cards are not only used in smartphones and tablets but in various IoT sensors and devices from smart thermostats to large-scale manufacturing machines to autonomous vehicles. The thing is, IoT deployments are more demanding than our day-to-day usage of mobile devices, and often require the device to switch between networks seamlessly, often when they move between countries, as in the case of autonomous vehicles, drones, and other mobile IoT machines.

This is where the eSIM comes in.

What Is The eSIM Card?

First, the term ‘eSIM card’ is actually incorrect since an eSIM no longer comes in the form of a physical card.

Instead, en eSIM comes in the form of a very small chip (6mm x 5mm x 1mm) that is soldered into the device’s body. This is where the name eSIM, which is short for embedded SIM, comes from.

The eSIM card has two main characteristics that differentiate them from standard SIM cards:

• Durability

Since the eSIM is soldered into the device and is protected by the device’s shell, it is more durable than standard SIM cards. Standard SIM cards can only last for around two years before we’ll need to replace them, and that is in normal daily usage. This is obviously not ideal in IoT deployments where devices are often deployed in remote areas with extreme conditions (high/low temperatures, vibrations, etc.).

The eSIM is much more durable and can last for up to a decade in harsh environments.

• Rewritable Data and Remote SIM Provisioning

Standard SIM cards are designed to hold a single SIM data from a single network provider. The information on an eSIM, however, is rewritable. This allows a feature we call Remote SIM Provisioning (RSP).

RSP essentially allows us to seamlessly switch between networks on a device without replacing the SIM card, typically via a mobile app that allows over-the-air, remote commands.

RSP is a very useful feature in IoT projects, allowing businesses to scale the IoT deployment to different countries while eliminating the hefty roaming charges, a common issue in IoT today.

The Advantages of eSIM in IoT Deployments

Based on the two characteristics above, there are several key advantages of using an eSIM in IoT projects compared to standard SIMs:

Cost-Efficiency In Switching Networks

The most important benefit of using an eSIM is that logistically it’s much easier and affordable to switch between different mobile networks.

If we are using standard SIM cards, we’ll need to replace the SIM card with a new one every time we switch between data plans and network providers. With an eSIM, we can easily switch to a different network with just a mobile app or a phone call to our network provider.

Versatility in Temporarily Changing To Another Network

The eSIM can store multiple SIM data at a time (typically up to five virtual SIM data). Meaning, in the event when a network is having trouble or the coverage for a specific network is sub-optimal, we can temporarily switch to another network to ensure the reliability of the IoT operations.

Use Less Space On The Device

Although the SIM card tray is already pretty small, the SIM will eliminate the tray, allowing device manufacturers more flexibility in designing the device. For example, manufacturers can use this space to increase the device’s battery size or add more features. Also, no sim card tray will also translate into one fewer hole in the device, which means more protection from moisture and dust.

Global Connectivity

By using the SIM together with an IoT data plan provider that supports global coverage, you can ensure global connectivity for your IoT projects. Whether you are planning to expand your IoT project at the moment or are planning for future scaling, this can be a handy feature to have to ensure your IoT deployment is future-proof and not confined by borders and geographical locations.

eSIM and Global IoT Connectivity

At the moment, cellular connectivity is the closest thing we have to a true global connectivity solutions, and the eSIM card is the technology enabling this by eliminating various common issues in IoT use cases:

• Cellular coverage is divided between different network operators, and when devices move between locations, we’ll need to switch into different operators. In such cases, we may be required to physically replace the device’s SIM card, which can be a logistical nightmare.
• Global connectivity across multiple carrier networks, countries/regions, and operating systems must be maintained, and very few cellular service providers currently offer this.
• We’ll need a comprehensive device management system that allows remote provisioning for individual devices or in bulk. This will also include the ability to perform OTA updates and security patches.

 

As a result of eSIM and RSP, we don’t need to switch to different SIM cards anytime the device needs to change network providers and/or move to different locations.

Thus, the eSIM offers more versatility in allowing global IoT connectivity, solving some key challenges of common large-scale IoT use cases.

Conclusion

An eSIM card is embedded or soldered into the device’s body rather than being a physical plastic card. The eSIM is rewritable with Remote SIM Provisioning (RSP) feature, which allows users to seamlessly switch between networks via over-the-air commands, eliminating the need to replace the SIM card every time we switch to another network.