eSIM : What You Should Know

eSIM (Embedded SIM) is an evolution of the SIM card for mobile phones and connected objects. Although the size of SIM cards has been reduced more and more, some “new” communicating objects, such as smartwatches, no longer have enough room to integrate a SIM card, even in nano format. And, above all, it is quite complicated to change the SIM card on connected objects. It was then decided to develop a new SIM card format, with two new features. The first is that the card can be soldered to an electronic board. The second, and most important, is that a protocol is being developed to provide the SIM card remotely and through the mobile network. It is thus possible to download profiles from different operators inside the eSIM without physically intervening on the SIM card.

eSIM is a method of identifying the user in the mobile network without a replaceable SIM card. The subscriber information is securely embedded in a non-exchangeable module of the mobile device. This module is either a small physical integrated circuit or a software enclave of the system-on-a-chip. This should replace the classic SIM card in the future.

The eSIM differs mainly in the provision by the mobile network operators from the already established, classic SIM card. If these were either sold in a shop or sent by post in the past, a customer can become an online customer of a mobile phone provider at any time with the help of the eSIM and use his mobile phone or another end device immediately, if the provider supports this feature. Once the profile is loaded into the mobile device, there are no significant differences to the use of a physical SIM card.

The first version of the eSIM architecture specification was released on December 23, 2015. In 2017, Qualcomm presented a technical solution, with live demonstration, embedding directly within its Snapdragon processor the hardware (the Secure processor and all the associated memory and calculation units) and the software (secure Java applications) to emulate the SIM card within the phone via the Snapdragon processor, therefore without a physical SIM card. The first device that could be equipped with a subscriber ID via the eSIM standard was the Smartwatch Samsung Gear S2 in its 3G version. In 2018, Google equipped the Pixel 3 3XL models and Apple equipped the iPhone XS, XS Max and XR models with support for the eSIM. While Android smartphones have been dual SIM capable for many years, for the first time iPhone models also have the option of operating more than one mobile phone connection in parallel.

Technical and Economic Interests of eSIM

In the case of a mobile phone (which is not necessarily the main use of eSIM) the advantages of eSIM are as follows:

1. Mobile phone manufacturers, by eliminating the physical SIM card, no longer have to manage a slot to physically connect the SIM card to the phone. This simplifies the design of the phone;
2. Mobile operators will no longer have to send a physical SIM card (with the data recorded on the SIM card), but will be able to directly download the information into the phone’s on-board chip;
3. Customers will no longer have to change the SIM cards in the phone in case of a change of carrier, the transition will be done instantly, simply by updating the data saved in the chip by OTA download;
4. There is, technically, no impossibility for the chip to be multi-operator, in other words, the phone can become “multi-SIM” and “multi-operator” if the manufacturers decide to do so.
5. According to the manufacturers, the eSIM could allow a completely dematerialized customer journey.
6. Indeed, it is now necessary, after subscribing to a mobile offer, to obtain a SIM card containing all the information of the customer profile, which is then inserted into its terminal. The eSIM makes it possible to overcome this step. With the eSIM, you buy a terminal with an eSIM, and then download the operator’s data.
7. In addition to being able to download customer data remotely, another advantage is to be able to multiply the connected objects attached to the same mobile offer with a unique phone number. For the moment, these are mainly connected watches, but the range of products will be able to expand to tablets and cars.

Advantages and Disadvantages of eSIM

With the increasing spread of eSIM-enabled devices and special tariffs, it could slowly but surely come to an end with the classic SIM card. The eSIM makes mobile communications more flexible, cheaper and ensures unrestricted reception – similar to dual SIM smartphones, only without inserting and changing the SIM card. In this way, the eSIM can also be used to circumvent any existing weaknesses of the previous mobile phone contract. While the existing initial contract is the basic equipment for the customer, the additional eSIM offers the desired freedom. In this way, what is currently needed can be booked spontaneously and without a runtime commitment.
Similar to the SIM card, the eSIM also stores personal data such as address book entries or the subscriber’s mobile phone number. eSIM providers have the following security measures enabled by default:

• The eSIM profile is encrypted during installation.
• Asymmetric methods ensure the end-to-end transmission between the servers of the eSIM provider and the module of the end device.
• Each device can only decrypt and install the eSIM profile assigned to it.
• In terms of privacy, an eSIM is no worse than a SIM card. It even has the advantage that it cannot be lost or stolen from a device like the plastic card.

In theory, there are two potential disadvantages for the user with the éSIM:

• With the eSIM, the possibility of SIM swapping – and thus identity theft – has become a little easier for criminals. If the hacker has successfully passed off the mobile service provider as his victim and applied for a new SIM card, he no longer has to procure the new physical SIM – the built-in chip is described electronically with the eSIM profile.
• In addition, paranoiacs with the eSIM are no longer able to physically remove the SIM card as protection against cell phone tracking. However, you can delete the eSIM profile.
• With the disadvantages for mobile operators, it is not quite so simple: they run the risk that customers with the eSIM will switch to the competition much easier. Many carriers have not made any process changes in the procurement and activation of the eSIM.