eUICC – The Future for SIM Technology

Jul 5, 2019

Soft SIM, eSIM, embedded SIM, whichever name you want to use, it is certain that the recently standardized eUICC specification will change the way we look at IoT SIM cards forever, and disrupt the entire connectivity chain from manufacturer to service provider. But what is this super spec anyway? And why does it matter? Wonder no longer.

eU What?

SIM card comparisonThe current generation of SIM cards use a UICC (Universal Integrated Circuit Card), which stores information and applications securely
for the SIM profile, and in this case, eUICC is really just an improved, embedded version of that secure technology. The first important thing to remember about eUICC is that it is not a new ‘form factor’ of SIM card like mini (2FF), micro (3FF), or nano (4FF) SIMs, and instead restructures the SIM to allow for multiple profiles on one card. There has been a new form factor introduced alongside the eUICC spec, MFF2, which is smaller and more resistant to heat, cold and dust, but is not used in every case that eUICC is useful.

Traditionally, (but not always) one SIM card holds one SIM profile, which holds all the information necessary for a SIM card to function, like the file system, operator keys, and International Mobile Subscriber Identity (IMSI), which are generally assigned to one operator and therefore give one connectivity option per SIM. This is where eUICC changes the game in a really big way: it effectively acts as a ‘container’ of multiple SIM profiles, so that one SIM card can hold several different connectivity options, and operators, at the same time, and choose between these options.

This is important because no one operator can guarantee complete uptime, fixed prices, or that their technology will stay relevant. This specification allows users to change their SIM profile if an outage occurs on a network, or if a network band is sunsetted, and maintain connection with a SIM profile that has been added to the eUICC ‘container’, without having to remove the SIM from the field.

Over the Air and Under Control

This is another key factor of the eUICC, the ability to remotely add or ‘provision’ SIM profiles Over the Air (OTA) whilst the SIM is embedded in a device, making it especially relevant to the coming industrial IoT revolution. This means that the relationship between manufacturer, user and operator will start much earlier, as operators will add their SIM profiles to the eUICC SIM at the point of manufacture, and end users will then be able to add or remove operators as they see fit, without ever removing the SIM from the device.

This freedom to change SIM profiles is policed by a secure architecture based around a certificate chain, whereby the root certificate authority is the GSMA or another regulatory body, who ensures each operator and profile is legitimate and has independent data streams and roles. Because of this secure architecture, the ability to provision and remove SIM profiles and to do it all without touching the SIM, once deployed the eUICC standard has a claimed life of 20 years, in which it can be modified indefinitely to manage new operators and network standards.

MVN-No Problem

Because the network architecture is designed this way, it means that no data can be transferred between ‘channels’ or profiles, as it requires authorization from the central certificate authority to determine a signal’s legitimacy and ensure that there is no interference between profiles. This architecture also means that if you wish to change your operator for any reason, while free to do so, you must first check that the Mobile Network Operator (MNO) that owns the network can be easily changed to the new operator. Because MNO’s lease bandwidth spectrum from that country’s regulatory body, they have to negotiate service rules, controls, and network infrastructure for themselves, and therefore come up with different Operating Support Systems (OSS) that users are subject to.

When switching between MNOs users have to check how easy it will be to adopt the new network infrastructure, service rules and controls, otherwise they may face a significant period of downtime without service at all. Mobile Virtual Network Operators (MVNOs), however, use the existing network infrastructures negotiated by MNOs, and so are not subject to the same rules and restrictions that an MNO is, as they can simply negotiate to use another network architecture with different service rules.MVN diagram

PodM2M goes one step further as an MVNO, offering multiple profiles in one, and therefore can switch between network infrastructures instantly, allowing the use of several profiles within one data channel. The eUICC can adopt this Multi-IMSI solution as if it is a single operator, but with the ability to instantly switch operators and share data between the ‘profiles’ that are contained in one channel of the
eUICC SIM. This also means that there would be no downtime when adopting the PodM2M profile, as it can use a network that matches the current profile.

A Connection Made to Last

With an eUICC specification in a 2, 3, or 4FF SIM, PodM2M’s multi-IMSI technology would extend this technology to its limit, allowing a user to embed their SIM at the point of manufacture with several independent channels active on the SIM, as well as a channel with the ability to transfer data between the profiles contained in it.

This would allow a user to keep their device connected for the maximum eUICC life of 20 years, while ensuring that there are multiple data channels that are separate from one another, some which can communicate with each other, and be able to add or remove profiles without worrying about MNO structures and rules. Once eUICC is rolled out fully, a pairing with PodM2M would remove all potential blockages and outage risks, leaving your application connected, without any extra fuss.