eSIM or embedded SIM in M2M (machine to machine) provides easy mobile connectivity to industrial IoT devices and all types of machines. Once a device is on the field, the SIM could be managed remotely, thus removing the need of a local technician to disassemble the device and change a SIM.
eSIM for M2M consists of 3 main parts : eUICC, eSIM profiles, and Subscription Manager modules.
The eUICC (Embedded Universal Integrated Circuit Card) is a chip similar to the classical SIM that everybody knows, which comes with an operating system designed in accordance with the standards that define the remote SIM provisioning. These SIMs come in different form factors, depending on the target device needs, the most common format being MFF2, which is an SMD chip that will end up soldered in the device.
Some of the benefits of having the eUICC soldered in the device are:
- hermetically sealed
- smaller devices
- reduced production costs
The eUICC comes with a pre-loaded profile, usually referred to as bootstrap.
The eSIM profiles are digital SIMs based on the industry standards that allow the use of a cellular plan without having to interact with a physical SIM. eSIM profiles are managed by the Subscription Manager modules and are downloaded and installed on the eSIM.
The eSIM could store multiple Profiles which could be either in state Enabled or Disabled. Only one Profile could be in state Enabled at a time and this profile will provide cellular connectivity.
Two benefits of having multiple Profiles are that they could be given the Fallback attribute and Emergency Profile attribute. Having a profile with Fallback attribute will guarantee that when connectivity is lost (for example, when driving on a road with poor network coverage) in the current Enable profile, the eUICC will switch to the profile having the Fallback attribute and the device will continue to have cellular connectivity with this profile.
The Emergency Profile attribute could be used in automotive. When the car is involved in a crash, it switches to this profile and notifies the local emergency services about the incident, GPS location, airbag status and number of participants in the car.
The Subscription Management for M2M is split in 2 main components: SM-SR – Subscription Manager Secure Routing and SM-DP – Subscription Manager Data Preparation. These components should be designed according to SGP.02 standard and should be interoperable regardless of vendors.
The SM-SR is responsible of storing the information about the eSIM (EIS- eUICC Information Set) and for establishing a secure communication with the eSIM on the field to send remote management commands: download and install, Enable, Disable, Delete, Set Fallback/Emergency profile attribute. An SM-SR and the eUICCs stored by it could be owned by the device manufacturer (for example an automotive manufacturer) and could be linked to one or multiple SM-DPs owned by mobile network operators.
The SM-DP is usually owned by a mobile network operator and is responsible for storing the profiles and preparation of download into the eUICC. The SM-DP could be linked to different SM-SRs.
The use cases for eSIM in M2M are seen in automotive and industrial IoT, such as smart meters, POS and sensors.
In the European Union it is mandatory to have eCall (emergency call) in all new cars. Having the eUICC soldered directly in the factory in an automated process is cost-effective. Once the car has the target country defined, the download and installation of the most suitable Profile could be initiated by SM-DP to reduce roaming costs. Some car manufacturers are selling connectivity plans which provide internet to the infotainment system and allow the cars to receive over the air software updates. Having the possibility of changing eSIM Profiles remotely and removing the need for the car to be serviced make it more customer friendly and cost effective.
Smart meters are devices that measure electricity, natural gas, water and heating consumption. These devices record the consumption and time intervals and send the information to the utility provider for billing purposes and system monitoring. The meters could provide detailed information to the consumer to have a better understanding of the consumption behavior. Such meters require connectivity which could be provided by eSIM for M2M.