IoT Device with eSIM Support

 Subscriber Identity Module (SIM) has become de-facto way to authorize mobile device to Mobile Network Operator (MNO) network. Starting as plastic card as it’s physical form, SIM has evolved in some stages from regular, micro, nano, and now it has another form as eUICC SIM (eSIM). Plastic SIM works well for consumer devices and many IoT devices as long as it works in normal temperature environment.

When it come with IoT devices there are some challenge that plastic SIM need to overcome.

§  IoT devices deployed globally and it need to switch MNO connectivity with better coverage in terms of quality.

§  IoT devices need to avoid roaming restriction.

§  IoT device connectivity need tobe easily managed and maintained, even if it is located in far distance location.

§  We need to move away from complexity of physical SIM logistic and management.

 

One benefit of eSIM that it can contain more than one MNO profile which required for network authentication. The first and second challenges above find the answer on this. eSIM is a GSMA global specification and it maintains the equivalent level of security and protection offered by traditional SIM. On first connection, an eSIM uses a preloaded bootstrap profile and then connects to a MNO network to perform an initial profile transaction. After that eSIM can switch the profile to the one which has better coverage and roaming plan.

If IoT device installed in difficult-to-access locations, paying a field technician to change a SIM card becomes inconvenient and costly. With eSIM the profile switching and update can be done remotely  by OTA.

From the faced challenges it can be understood that IoT device with eSIM support has become significant aspect.

Inside the eSIM there is a component Local Profile Assistant (LPA) that need the device support to work properly. So in terms of that an IoT device needs  below general capabilities to work properly with eSIM.

 

Boot profile handle.

When there is no operational or test profile enabled on eSIM, the default boot profile is enabled. The modem recognizes the eSIM with the default boot profile enabled as a valid SIM, reports the card as valid to upper layers, and doesn't turn off the SIM power.

Sending terminal capability.

On power-up, the modem sends correct terminal capabilities to the eSIM. The terminal capability encodes support for eUICC capabilities Local Profile Management and Profile Download.

 Support OTA for eSIM OS update.

The modem supports all requirements for eSIM OS OTA updates, for example, switching to passthrough mode and keeping the eSIM powered on during the OTA update procedure.

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