What is iSIM?

Istvan Lajtos

Head of Product Management

LinkedIn

What is iSIM?

iSIM stands for “Integrated SIM” and is an evolution of SIM technology where cellular connectivity and subscriber identity management functionality are integrated into a System-on-Chip (SoC).

Unlike traditional physical SIM cards that need to be inserted or embedded into a device, moving the SIM into a SoC reduces the footprint required on the device for connectivity components.

How does iSIM work?

A SoC for cellular connectivity would typically include a microcontroller, cellular modem and the SIM, which includes the SIM operating system, applications and a secure vault for storing sensitive data, such as mobile subscription identifiers.

The purpose of SIMs is to ensure that devices authenticate and connect securely and reliably to networks and the cloud. Removeable and embedded SIMs are hosted in exceptionally secure chips, similar to those used in bank cards. They’re designed – and tested – to resist highly sophisticated physical and logical attacks.

Challenges of iSIM for IoT

The challenge for SoC manufacturers is to design chips with advanced security mechanisms that can detect possible attacks and provide the same levels of resistance as existing SIMs.

To meet the security requirements, the iSIM is contained within a Tamper Resistant Enclave (TRE), also known as a secure enclave. Recognised by the Trusted Connectivity Alliance, a TRE uses hardware and low-level software capabilities to provide hosting for secure applications and their confidential and cryptographic data.

SoC manufacturers need to achieve GSMA certification for their iSIM chips if the technology is going to be trusted and adopted widely.

Benefits of iSIM for IoT

Built within a secure enclave in the SoC to GSMA specifications, iSIMs provide the same levels of identity authentication, security and seamless connectivity as embedded SIMs.

But the benefits of iSIM technology over SIMs of other form factors can also address issues that are holding IoT back.

• Small size – reduced footprint for connectivity components
• Less power, more performance
• Reduced risk of damage for ruggedised devices
• Reduced production cost and supply chain complexity
• Root of Trust (RoT) support for secure and edge applications

Choosing a connectivity solution for your device

For any connected device to deliver on its promise, it must have access to a secure, reliable connection. Are you looking to produce and deploy IoT devices but not sure which connectivity solution you need?

Our article, “Cellular IoT Connectivity: What Business Leaders Need to Know” provides valuable insights for achieving success in cellular IoT. It covers topics such as selecting the optimal network, maximising coverage and uptime, and addressing connectivity design considerations for your device.

Istvan Lajtos

Head of Product Management

LinkedIn

Istvan’s telecommunications career spans more than twenty years in a variety of roles, including product management, technical account management and marketing. Istvan leads on product management with expertise in communication technology strategy development, smart city technology and IoT, 4G to 5G mobile network evolution to secure content delivery.