eUICC and eSIM - are they the same thing?

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You would be forgiven for thinking that eUICC and eSIM are the same thing, given that they are being used interchangeably by a lot of media sites and blogs. The reality is, however, that they are two different technologies.

In this article we will define precisely what eSIM and eUICC actually are, and talk a little bit about the different benefits that they offer.

So, what exactly does eSIM mean?

SIM stands for Subscriber Identity Module and is often used to refer to the small card shaped chip that is inserted in to smartphones and other mobile connected devices. The SIM enables a device to be recognised on the carrier network and identified by the number associated with it.

Traditional SIM cards have been through a few iterations throughout the lifecycle of the technology. It’s perhaps hard to imagine now, but the the first SIM actually resembled a credit card in size and weight! This is the first form factor of SIM, or 1FF as it referred to in the industry.

Subsequent forms of SIM have been the mini-SIM (second form factor, or 2FF), micro-SIM (3FF) and most recently the nano-SIM (4FF).

There is now also another form factor, the MFF2, which are machine-to-machine (M2M) SIMs. This is the preferred form factor for connected devices including cars, appliances or really anything that is IoT-enabled.

Confusions arise when people assume that an embedded SIM (eSIM) must be a machine-to-machine (M2M) SIM.

In fact, eSIM is a technology that can be present regardless of form factor. Take the relatively new iPhone XR for example, it accommodates a physical SIM but also has an eSIM built in, allowing users to purchase a plan from another carrier and use it alongside their contracted calls, messaging and data plan.

One huge benefit of this for anyone who frequently travels internationally is the ability to avoid roaming charges by purchasing a temporary eSIM from a local carrier, provided one is available.

What, then, of eUICC? If eSIM is already so developed, what more does eUICC offer?

What does eUICC do that an eSIM can’t?

It might be helpful to draw a comparison between old and new - physical and embedded - when looking at eUICC, just as we did with eSIM.

The Universal Integrated Circuit Card (UICC) does a lot more than the Subscriber Identity Module (SIM). In fact, it runs the SIM application whilst also storing various pieces of information such as the user’s contacts list, enabling the use of mobile data and managing data roaming across multiple carriers.

It is actually more accurate to refer to the form factors we discussed above (1FF, 2FF etc.) as UICC form factors rather than SIM form factors, because the removable card is actually the UICC. Technically the SIM is just one of many things that exists on the UICC.

So, there can be no SIM without a UICC. However, when the applications that run on a removable UICC instead run on circuits that are embedded within a given device, then we have an eUICC-enabled device.

This offers different benefits to an eSIM setup. The most notable benefit is the ability to run over-the-air (OTA) provisioning of multiple SIM profiles across multiple networks from a central management point. Once provisioned, the SIM profiles that exist on an eUICC can be remotely managed and, if necessary, deleted.

This means that whilst eSIM may be useful for individuals, eUICC is an extremely useful technology for businesses and manufacturers.

OTA provisioning and management offers a level of flexibility that was simply not possible before eUICC was invented. IoT devices with eUICC technology can connect anywhere in the world and stay connected in the event of multiple carrier outages. User devices on an eUICC network can also be migrated in their hundreds in a matter of moments, and we are still only in the early stages of the technology’s lifecycle.

JT IoT offers a wide range of solutions designed to maximise the potential benefits of both eSIM and eUICC for your business. Get in touch to find out how our solutions can help you grow your business, increase your operational efficiency and enhance your end-users’ experience.

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To learn more about IoT SIMs, check out our quick guide to everything you need to know about IoT SIMs.

Interested in learning more about JT eSIM solution? Contact one of our IoT experts.


Filed Under: IoT SIMs, SIM Form Factor, eSIMs, eUICC