Skip to main content

Back to articles

What is an IoT SIM card? Everything you need to know

Hologram IoT SIM Card

Learn about how IoT SIM cards are transforming cellular IoT and how industries communicate. Here’s everything you need to know.

Maggie Murphy

January 28, 2022

IoT applications have unique demands. When thousands or even millions of connected devices need to communicate with each other and the cloud with little human oversight, they require SIMs that differ from those used in traditional mobile phones. Enter the IoT SIM card, which is distinctive from the traditional SIM in a few significant ways.

Click the links below to jump to what you need:

What’s the difference between traditional SIMs and IoT SIM cards?

5 industry use cases for IoT SIM cards

IoT SIM card form factors

Future-proof your network with Hologram

What's the difference between traditional SIMs and IoT SIM cards?

Because IoT devices typically require wider geographical ranges, more adjustable lines of service, and higher levels of encryption, management and control than consumer cellular devices, IoT SIM cards must function a little differently. Let’s take a closer look.

Recommended reading: What’s the difference between SIM card types?

How do traditional SIM cards work?

A traditional subscriber identity module (SIM) card stores data about its user, including the international mobile subscriber identity (IMSI) number and its key. The IMSI is used to identify a specific line of service that the user’s data plan is attached to. Every SIM card also contains an integrated circuit card ID (ICCID), a 19- or 20-digit number that’s typically printed on the back of the card. The ICCID is a globally unique serial number that serves as a signature to identify the card. Some SIMs also store contact information and even run software.

Ultimately, the SIM serves as a link between a cellular device and a network. A traditional SIM within a consumer device typically carries a personal cell phone number and data so that the service provider knows which plan you are on, how much data you’ve used, and other details. Normally, traditional SIMs are provided by your carrier and follow a basic setup process:

1. Insert the SIM card into your phone.

2. The card connects with your service provider.

3. Through that connection, your service provider attaches your personal phone number and data plan to that particular SIM card.

4. The SIM card is now your personal connection with your provider. This allows you to put the SIM into any compatible mobile device and access the same phone number and stored contacts.

How do IoT SIM cards work?

IoT SIM cards work in much the same way as traditional SIMs — they establish a connection, authenticate it, and monitor and store important information such as physical location.

Both IoT SIMs and traditional SIMs contain basic identification information such as the ICCID, IMSI, authentication key, and location information.

Installing and activating an IoT SIM may follow a slightly different process than a traditional SIM. For example:

1. The device is equipped with either a removable IoT SIM card or embedded SIM (eSIM).

2. The device connects with the service provider — often a provider tailored to IoT use cases, providing LPWAN connectivity or other distinctive features.

3. The device establishes a connection, authenticates it with keys, and establishes its location.

Recommended reading: What is cellular IoT? The future of IoT connectivity

5 industry use cases for IoT SIM cards

IoT SIM cards enable cellular IoT use cases, providing benefits to many industries. Let’s take a closer look at a few examples.

1. Retail

By allowing companies to keep a closer eye on their supply chains, inventories, sales, and customer reactions, IoT technology enables many useful applications in retail. Here are a few:

Shoplifting prevention

IoT asset trackers attached to retail products could make shoplifting nearly impossible — if someone steals an item, the store can trace it so long as the tracker is still attached. Some retail stores also use cellular IoT sensors to track in-store assets, such as shopping carts with products like CartTrac from Bemis Retail Solutions. CartTrac allows stores to track down missing shopping carts both outdoors and indoors using GPS technology.

Cashless payment systems

Customers who agree to have their information cataloged could simply walk out of a store with their purchases. IoT tracking devices on the items, along with facial recognition software, can keep track of the items customers pick up and charge them as they leave. Amazon is piloting this type of technology with their Amazon Go cashless convenience stores.

2. Healthcare

Connected sensors and wearable IoT devices are improving patient care and helping facilities improve operations. Here are a few interesting applications of cellular IoT in healthcare.

Smartwatches

To provide a flow of data in real-time, wristband devices that track health information need to stay connected to a network no matter where their wearers go. Elderly users who need their heart rate and vitals continuously monitored can move more freely without worrying about being out of range of their Wi-Fi, and alerts can be relayed in real-time if an emergency arises.

Health monitors

Small cellular IoT devices can deliver highly accurate data to physicians in patients with chronic medical conditions, such as diabetes. Readings like blood glucose levels or electrocardiogram data can be sent directly to physicians. Having a device tailored to monitor this health information allows for a higher degree of accuracy in potentially dangerous medical situations — and using cellular technology to connect these devices means they can operate more consistently.

3. Manufacturing

IoT plays a pivotal role in realizing Industry 4.0. Connected sensors are placed on factory floor machinery and the data they yield can be used to predict maintenance needs, monitor workflows, drive productivity, and feed into larger company databases to run analytics reports. Here are a few applications for cellular IoT in this field.

Manufacturing robots

Incorporating cellular IoT into manufacturing robots is useful on many levels. If the robot is a mobile unit, it maintains connectivity despite its location. And with manufacturing locations spread around the world, the likelihood of a strong cell signal is much higher than a reliable on-ground high-speed internet connection.

Predictive maintenance

Knowing ahead of time when a factory robot is on the verge of breakdown is a huge advantage for manufacturing companies. IoT devices can provide that advance notification, allowing operators to deal with emerging problems before they cause unexpected (and costly) downtimes. Such predictive maintenance requires stable connectivity, but some manufacturing operations take place in remote areas — especially those used for harvesting raw materials. For example, a remote stone quarry may not have high-speed LAN connectivity, yet its machinery still needs careful maintenance. A cellular connection allows IoT devices to monitor those machines as closely as other machines in well-connected factories.

4. Logistics

IoT logistics applications can help companies connect global supply chains and keep track of the movement of goods and vehicles in real-time.

Monitoring goods in transit

Many products, materials, and chemicals are sensitive to changes in temperature and humidity. Cellular IoT devices allow these factors to be tracked in real-time to ensure the safe arrival of volatile materials — whether it’s a shipment of ice cream or medication.

Transportation route management

Advanced fleet management systems detect traffic and weather conditions along a vehicle’s route and recommend alternate routes as needed. Fleet-wide, this reduces fuel consumption and yields other benefits in saved time and increased safety. Cellular IoT makes these applications possible by providing stable connectivity and constant updates.

IoT SIM card form factors‍

SIM cards come in various sizes or form factors. When the first SIM cards appeared, there was only one form factor: the credit-card-size 1FF. Today, there are four standard sizes of removable SIMs, along with the embedded SIM (MFF2). As mobile phones shrank over the years, so did their SIM cards. IoT SIM cards come in the same form factors as traditional consumer SIMs.

While form factors denote different casing sizes, the chip itself remains the same size — with the exception of the MFF2 (embedded or eSIM), which is smaller. Here’s a brief overview of the SIM form factors available for IoT SIMs:

  • Mini SIM (2FF)

At 25mm x 15mm x 0.76mm, the Mini SIM is the largest removable SIM card currently in use. It’s been around since the mid-1990s when it emerged as a smaller option (at the time) for shrinking mobile devices. Today, the Mini SIM still works well for larger connected devices, like cars and vending machines.

  • Micro SIM (3FF)

The Micro SIM measures 15mm x 12mm x 0.76mm, significantly smaller than the Mini SIM. It’s large enough to be manageable for easy physical swapping of SIM cards, but it fits better in mid-size IoT devices like tablets and telehealth monitors.

  • Nano SIM (4FF)

Measuring at 12mm x 8.8mm x 0.67mm, the Nano SIM is both smaller and slimmer than its counterparts. It’s an ideal solution for compact IoT devices, including wearable technology and mobile payment equipment.

  • Embedded SIM (MFF2)

The embedded SIM or eSIM is soldered directly to the device’s motherboard, so it’s fully encased in the device. That means it’s a great choice for IoT devices deployed outdoors or in harsh conditions. For large-scale deployments, choosing an eSIM can also simplify your supply chain because it removes the step of physically installing a SIM in every device. There’s often confusion around the term eSIM, as many people use it to refer to eUICC-enabled eSIMs. But the eSIM itself is simply what it claims to be — an embedded SIM — and does not automatically enable remote provisioning. More IoT designers are starting to embrace eUICC-enabled eSIMs because of their versatility and flexibility. (For more on that, check out our eUICC SIM platform, Hologram Hyper.)

Recommended reading: What is an eSIM and how is it changing industries?

Future-proof your network with Hologram

No matter its size and intended use case, every IoT device needs a dependable source of connectivity. Hologram’s IoT SIM card offers seamless, global coverage for IoT devices with access to LTE/4G/3G/2G technologies. With our Hyper eUICC-enabled SIMs, you’ll gain access to new connectivity partnerships without any additional carrier negotiations, integrations, or hardware swaps.

Get started with Hologram today

Talk to an IoT expert
Receive a free SIM
Customize your plan