Demystifying Technology: Embedded-SIM (eSIM)

Phone with eSIM Technology
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It seems every day we discover more and more services and activities that can be done virtually, showing that the world at large has indeed “gone virtual.” The servers that you, your apps, your smart TV, and IoT devices all connect with more than likely also connect with a virtual server that is hosted in datacenter or a cloud datacenter. This virtual renaissance also applies to the well-known SIM (subscriber identification module) card; embedded-SIMs, or eSIMs, are virtual SIM cards that are embedded in the hardware of your mobile device, so you do not have to worry about inserting physical SIM cards into any slots.


What Is eSIM?

eSIM is the evolution of the SIM card, that little piece of plastic we have been putting into our mobile devices for decades to allow them to connect and securely authenticate on GSM mobile networks to make/receive phone calls and later send/receive data (e.g., emails, Internet browsing, social media) using 2G, 3G, 4G, and most recently 5G networks.


But rather than another smaller/thinner piece, like previous evolutions were (e.g., mini-SIM, micro-SIM, nano-SIM), with eSIM we are talking about an embedded hardware chipset than can store not only one but multiple operator profiles on a single device simultaneously.


More than Just Dual SIM

Having several different phone/data lines at the same time is indeed nothing new, as the Dual SIM technology would already allow having two different SIM cards on the same device. However, this was only available on a small number of mobile devices, only for physical cards, and with some serious limitations (e.g., 4G and/or data only available for SIM 1, with SIM 2 limited to 3G phone calls), which explains its mild success in the consumer market and almost zero presence in the enterprise world.


eSIM on the other hand offers virtually limitless possibilities for both consumer and enterprise users, as it is supported by the main manufacturers (e.g., Samsung and Apple), allows for several SIMs, and is ready for enterprise usage, where separation of work life and personal life is required.


Balance Work and Personal Life, from Anywhere, Securely

Balancing work and personal life have always been a major goal for most corporations where BYOD (Bring Your Own Device) and/or COPE (Corporate-Owned, Personal Enabled) programs are in place. In practice, this has proven to be a little more complicated when it comes to separate phone calls and data usage. However, with eSIM, both scenarios are covered; either the device is personal or corporate-owned, the enterprise can provision a work profile for work-related calls and pre-approved work apps data usage, then the end-user can simply stick his personal SIM card into the device and have it used for private phone calls and personal apps data usage – all this managed using a UEM (Unified Endpoint Management) software solution.


The COVID-19 pandemic has forced millions of employees all around the globe to work from home, independently of most enterprises being ready for it.


When it comes to security, one concern is that these users would mainly use their home Wi-Fi network to connect to the Internet and access corporate resources as securely as possible, directly on the cloud or behind guarded walls. Unlike an internal corporate network, this Wi-Fi network is not managed by the enterprise, so there is no way to enforce the recommended level of security (e.g., enforce WPA3), plus it is shared with many more devices and users. The same applies when employees are on the road, connecting from their hotel room, airport, or unsecure Wi-Fi networks when visiting a customer. This is where eSIM steps in, providing corporate devices with a secure alternative to connect from anywhere, using 4G/5G networks, not only on mobile device like smartphones and tablets, but also mobile desktop computers like laptops.


This is also a very flexible option for business travelers, for example those visiting their office in another country or region for a couple of days or weeks where additional expensive charges are usually incurred. In that case, a third line could be provisioned (for example, data only) to be used instead during that stay abroad, so neither the home, private nor work lines are used, but instead that one-time local subscription (e.g., 4G for 3 weeks). Note that although most manufacturers allow multiple eSIM profiles, usually only one of them (together with physical SIM) can be enabled at any given time.


Easier Deployment, Lower Cost

eSIM has revolutionized the way voice/data subscriptions are provisioned for mobile devices. In the past, enterprise would need to wait for the operator to send them via mail or parcel, then have each of the physical SIM cards stuck into the correct mobile devices. This does not seem like much when done at a low, private scale, but image deploying that for 100 or 1,000 devices is very time consuming – lots of repetitive, manual tasks prone to error.


With eSIM, it is as simple as scanning a QR code from the mobile device, or installing the operator app and authenticating, and then the new profile/line is added and ready to use in questions of seconds. The same happens when changing devices; the eSIM profile can easily be transferred from one device to another, if supported by both the device manufacturer and mobile operator. This is easier for both customers and telecom operators, as there is no need to maintain large physical inventories anymore.


On-Demand Activation

QR code activations work well when performed individually by each user or by a dedicated Service Desk team for small deployment, but it is difficult to scale in large deployments. However, using Entitlement Server or an MDM solution can fully onboard a new device, including eSIM activation, in one process. This is where the on-demand activation feature comes into play, which allows remotely and automatically provisioning eSIM to mobile devices upon activation.


Lifecycle Management

This allows customers to not only provision, but also deprovision/decommission/deactivate eSIM from managed devices when needed (i.e., if the device is lost, stolen, retired, wiped, etc.) – and all this can be done remotely. Enterprise can now manage both devices and their connectivity together, instead of separately.



The amount of logistics required for mobile operators to manage physical SIM – from assigning to a subscription in their internal system, to shipping them to the retailers and/or customers – is gargantuan. eSIM simplifies that immensely, as they will not need to deal with physical items anymore but service/subscription instead. Plus, previous SIM are made of plastic (Polyvinyl chloride, commonly known as PVC), so reducing if not eliminating their use is a great step to ensure lower environmental impact.


Wireless operators are not the only ones saving costs. Customers themselves are saving from a logistical perspective, as detailed earlier, and from a mobile budget perspective, as most operators allow using them on more than one mobile device using the well-known multi-SIM feature, and so combining all voice/data usage into a single plan, per-user, is a lot cheaper than having one per device.



Now that we have cleared up the mystery around eSIM and discussed advantages such as ease of deployment, flexibility between corporate and personal devices, allowing you to have more than one SIM, not having to keep track of physical SIM cards and cost-savings, among others, you may see the value in implementing it for your organization.


In deciding whether or not to deploy eSIM it is important to understand your business use cases, and the team at ISEC7 can help you determine how eSIM fits into your digital workplace, as well as helping with deployment. We would be happy to answer any questions you may have about eSIM and how you can leverage it for your organization. Please feel free to contact us with any inquiries you may have.


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(C) Rémi Frédéric Keusseyan, Global Head of Training, ISEC7 Group