nuSIM – the integrated SIM for the Internet of Things

Apple, Google and Samsung are using it, as are Audi, BMW and Mercedes: the embedded SIM, or eSIM for short. In contrast to the physical mini, micro and nano SIM cards, manufacturers solder this integrated SIM as a tiny chip directly onto the circuit board of a smartphone or a car’s communication unit. The advantage: Hardware components such as the slot for the SIM card and the data port become superfluous – and therefore no longer need to be considered when designing a device. The space freed up is now available for other components or is saved on altogether.

Companies are already using embedded SIMs in applications for the Internet of Things (IoT), for example as a permanently installed component of a sensor module, a telematics unit or a construction machine. But since it offers all the functions of a conventional SIM card, it is a complex piece of technology – and the costs involved mean that it’s therefore not suitable for all use cases.

In scenarios such as smart parking, networked street lamps and garbage cans, or environmental sensors in buildings and cities, intelligent radio modules are used on a massive scale; which means every cent saved counts. Deutsche Telekom and leading technology partners have developed the nuSIM especially for these cost-sensitive IoT applications and the NarrowBand IoT network (NB-IoT) created for them.

80 of the world's leading operators and service providers now support eSIM technology. In order to establish nuSIM as a worldwide standard on the Internet of Things, Telekom and its partners rely on an open ecosystem for mobile operators, chipset manufacturers, module suppliers and providers of digital security solutions. In June 2022, the first modules with integrated nuSIM will be available.

The nuSIM dispenses with the functions of the eSIM that are superfluous for many IoT scenarios. A smart meter, such as a networked water or electricity meter, for example, might send a tiny data packet into the network once a day. No voice or SMS functions are required. Features such as the SIM Toolkit access service, the Java Card programming language or over-the-air access for profile changes have also been left out. Module and device manufacturers program the operator profile directly onto the chip during the production process. As a result, the nuSIM offers the end user out-of-the box mobile Internet access.

This makes the nuSIM extremely slim and cost-effective. In addition, it requires less energy than an eSIM and thus extends the battery life of IoT devices. This makes it perfect for use in NB-IoT networks where energy and cost efficiency are key features. If required, the nuSIM can also be adapted to the IoT wireless network standard LTE-M.

The nuSIM is also less sensitive to shocks or large temperature fluctuations than the SIM in a card slot. That’s an advantage when used in Industry 4.0, for example in a factory or on a construction site. The absence of a slot also makes possible the closed design of a device and protects it from moisture and dust. The nuSIM thus achieves a service life of at least 10 years, in other words it usually lasts as long as the component itself.

In addition, it’s almost impossible to access a nuSIM soldered into a device in order to manipulate it. The security level corresponds to that of a changeable SIM: The login information stored in encrypted form on the SIM enables secure and private access to mobile networks and guarantees the integrity of billing – which is particularly important for roaming, for example when a truck with a tracking module is driving across Europe.