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What is an iSIM?

If you’re wondering what an iSIM is, and what it means for IoT connectivity – you’re in the right place! Here, we explain exactly what iSIM means, and how eSIMs and iSIMs differ, as well as where physical SIM cards fit into the connectivity landscape.

What is an integrated SIM?

Integrated SIM (iSIM) is another form factor and an alternative to traditional SIMs, where physical SIM cards were removable, and placed into devices, whether this was mobile phones, IoT devices, or smaller devices such as wearables and sensors. Instead of a physical plastic card being placed into the device, an iSIM is placed onto the device’s System-on-a-Chip, or SOC.

What’s the Difference Between eSIMs and iSIMs? 

You may have heard of embedded SIMs (eSIMs) and think that iSIM and eSIM sound basically the same. However, while an eSIM will be soldered to the circuit board of the device, the way iSIM technology works, can actually allow for a lot more flexibility and security.

This is partly because with iSIM, the SIM is integrated in a TRE, which stands for Tamper Resistant Element, which is on the device SOC. It’s not its own separate processor, so it uses a lot less power. You can activate an iSIM wirelessly using a secure protocol which is accepted and utilized across the industry, and you won’t need any specific SIM hardware.

How Does System on a Chip (SOC) Work?

To understand iSIM, we need to get a better view of what it means to integrate with the device SOC. A complex IoT device may have a number of different tasks to complete, such as connecting to WiFi, processing audio, visuals, or even tactile sensations, graphics processing, and sending and receiving data. Using multiple chips adds to the cost and the complexity of manufacturing devices.

By integrating the SIM directly into the SOC, and hosting the operating system of the SIM on the same chip, costs are heavily reduced, alongside power consumption – critical for battery-powered IoT devices where battery life is so important. By reducing the footprint on the printed circuit board (PCB), enterprises and device manufacturers can save costs by simplifying their bill of materials, while also reducing space and power consumption.

What are the Benefits of iSIM?

There are many benefits to using iSIM over traditional SIM technologies. Let’s look at just a few:

Size: Practically speaking, an iSIM is the smallest of the SIM technologies, much smaller than even an embedded SIM, which was already much smaller than a nano SIM! An iSIM is less than 1 millimeter squared. This saves space inside a device so that device manufacturers can add other components, or even make the device itself smaller as a whole, which is often cheaper to make and more appealing to customers.

Security: iSIM specifications are recognized and regulated by the Trust Connectivity Alliance, and have a consistent standard in the industry. Integrated via the SoC design, the iSIM is protected from being tampered with as it runs on a secure enclave, directly built into the chipset itself. As an iSIM cannot be removed, it’s much harder to tamper with or damage, and it also makes it more difficult for anyone to steal the phone and get away with using it themselves.

Resources: Both in terms of power consumption and cost, iSIM is a leap forward. An iSIM can be configured to reduce standby power consumption compared to designs that use a multi-chip approach like eSIM, opening doors for massive IoT. As an iSIM has fewer components and simplified design, manufacturing and logistical costs can also be heavily reduced.

Compatibility: iSIM is compatible with 2G, 3G, 4G and 5G networks, and is not tied to any specific network requirements. Its specifications have been standardized by the GSMA, as well as other global organizations that include 3GPP and ETSI. As it can be used by multiple networks at the same time, devices can switch OTA because of location, cost, or simple preference.

Use cases: Because an iSIM is so small, and because it’s so widely accepted in terms of communication standards and compatibility, the opportunities are endless for enterprises and device manufacturers to think of new and innovative business models. iSIM can be used in Utilities for electricity or gas meters, in medical equipment and wearables, for logistics use cases, in vehicle telematics systems, and beyond.

How Does floLIVE Use iSIM? 

At floLIVE, we work with our partners Kigen and Sony Semiconductors to leverage our one-of-a-kind IMSI library via iSIM, providing enterprises with compliant, multi-network local coverage for a wide range of IoT use cases.

Since one of the main purposes of iSIM is the reduction of physical size and power consumption, having a multi-IMSI capability with autonomous switching that has a low footprint and efficient power consumption is a key element in any multi-network solution. This is often not properly addressed by industry standards and other solutions in the market.

floLIVE’s multi-IMSI technology over iSIM is cost effective, has a low footprint, and ensures tight security and ultimate flexibility.

We work with all SIM factors, and our industry experience, global outlook, and customer focus put us best-placed to support the dynamic needs of a wide range of customers. We recognize that no fast-moving business can afford to be limited to just one SIM solution. That’s why we support plastic SIM, eSIM, and iSIM at the point of manufacture, as well as softSIM solutions OTA.

IoT device manufacturers and enterprises can launch, manage and scale their IoT projects worldwide, fully in line with all data privacy and compliance regulations, and with ultimate security, reliability and control.

Interested in learning more about iSIMs? Schedule a call with one of our IoT experts. 

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