What is an eSIM and what makes it special?

An eSIM (embedded SIM) is a chip permanently installed in the device that takes over the function of a classic M2M SIM card. Unlike a physical SIM card, the eSIM is not replaced but programmed digitally.

eSIM (embedded SIM): Compact and future-proof for IoT projects

An eSIM (embedded SIM) is a chip permanently installed in the device that takes over the function of a classic M2M SIM card. Unlike a physical SIM card, the eSIM is not replaced but programmed digitally.

The embedded SIM for IoT projects

Unlike the classic SIM card, which comes as a chip on a plastic carrier, the embedded SIM is simply a chip that is permanently installed in the end device. It measures around 5 x 6 millimetres and completely dispenses with the familiar plastic carrier. Instead, it is soldered in during production so that it is no longer necessary to insert a SIM card into the end device. This technology is playing an increasingly important role in M2M communication, as it transforms the networking of devices and creates new opportunities for IoT applications. The data for using the mobile network is uploaded via an electronic profile, typically using over-the-air methods.

Advantages of the eSIM for M2M communication

Space-saving

As the embedded SIM is soldered directly into the device, it takes up much less space in the end device than a conventional SIM card. This means that end devices can be made much more compact. The space that would otherwise be required for the M2M SIM and the SIM card slot can be used for other purposes or eliminated altogether.

Always the right format

SIM cards are available in different formats, but the eSIM is always the same. With an eSIM, there is no need to consider which SIM format is required for the device.

Conserving resources

An eSIM comes without a plastic carrier or packaging. This saves plastic waste and protects the environment. In addition, the SIM does not have to be sent to the user independently of the product, like a classic SIM card. This saves additional emissions for delivery.

Ready for immediate use

Instead of waiting until a SIM card is delivered by post and then inserted into the end device, the eSIM can be used immediately. The network operator data is transferred digitally and the device is ready for use.

Extended security aspects of the embedded SIM

A decisive advantage of the eSIM is the increased mechanical security. Because the eSIM is soldered to the circuit board of the end device, it is virtually impossible to steal the SIM card and misuse it for other purposes. The eSIM is also less vulnerable in environments with strong movements. A classic SIM card could, for example, slip in the SIM card slot and cause the connection to be lost. This risk is eliminated with an eSIM.

For sensitive applications, data encryption such as IPsec can be implemented in addition to mechanical security. This allows the transmitted data to be cryptographically secured before it is transported via public networks.

Technical integration and programming

The eSIM is programmed using standardized protocols. The GSMA eSIM standard makes it possible to load operator profiles onto the eSIM remotely. This is done via a secure management system known as the Subscription Manager. Subscription Manager-Secure Routing (SM-SR), which enables the secure management of eSIMs throughout their entire life cycle, is particularly relevant for IoT applications.

Embedded SIMs support various radio technologies such as LTE-M, NB-IoT and also LoRaWAN for energy-efficient applications. When configuring devices with embedded SIMs, parameters such as the MTU size should be taken into account to ensure optimum data transmission.

Application examples from practice

The possible applications for embedded SIMs are diverse and growing continuously:

  • Smart metering: Meters for electricity, gas or water can reliably transmit consumption data with permanently installed eSIMs.
  • Industrial plants: In production environments, eSIMs ensure a secure and robust connection between machines and plants.
  • Vehicle telematics: Embedded SIMs enable reliable data transmission in vehicles, even under harsh conditions.
  • Portable devices: For example, our eSIMs are installed in e-bike batteries for e-mobility solutions.

Realizing IoT projects with embedded SIM

At wherever SIM , we offer customized eSIM solutions for your IoT and M2M projects. Contact us for a personal consultation or test our products free of charge.

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