The network an IoT device selects significantly impacts the strength and reliability of connection, which is essential for seamless data transmission and optimal device functionality. Whether for a smart utility meter in a remote location or a fleet tracking device traversing different regions, the ability to leverage the best network is essential for maintaining service and achieving operational efficiency.
With the success of your IoT deployment at stake, it’s important to choose a SIM that will provide the connectivity your devices need to function. Zipit Wireless provides multi-carrier SIMs to enhance the reliability and performance of an array of global IoT devices and a robust platform to manage them. In this article, we’ll explain multi-carrier SIMs, how they choose a carrier, and how you can simplify the complexities of multi-network connectivity with an experienced connectivity partner.
What is a multi-carrier SIM?
A multi-carrier SIM supports connectivity to multiple carrier networks for reliable coverage in each area of deployment. When the signal is lost, the SIM can seamlessly switch to a different network to re-establish connectivity for global IoT deployments.
There are two types of multi-carrier SIMs:
- Global roaming SIMs are equipped with one profile, or IMSI, that is authorized to roam on other networks when the device is outside the primary carrier’s network, leveraging the best coverage in each region.
- Multi-IMSI SIMs store profiles from multiple mobile network operators (MNOs), allowing the device to capitalize on the strengths of local networks by connecting to the carrier with the strongest signal in each area of operation.
Global roaming SIMs and multi-IMSI SIMs both support global connectivity by accessing several carrier networks, but each is suited for different IoT applications. For devices that will mostly stay within a specific region, multi-IMSI SIMs provide optimal coverage in targeted markets. If roaming isn’t a necessity, leveraging the strongest networks within each market can provide more reliable and cost-effective global coverage.
The eUICC SIM (e-SIM) is another option with multiple IMSIs where you can add, manage, or remove carrier profiles remotely as needed. Whereas multi-IMSI SIMs keep all profiles active, e-SIMs can activate and deactivate profiles, improving operational and cost efficiency. The e-SIM offers improved flexibility, security, and scalability over other types of multi-IMSI SIMs.
On the other hand, some IoT deployments require a single SIM that works anywhere in the world. In such cases, global roaming SIMs from leading carriers enable seamless connectivity with just one product SKU. Zipit’s global roaming SIM leverages the strength of local networks for reliable, cost-effective global coverage.
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When should you use a multi-carrier SIM for your IoT device?
Some IoT devices are designed to connect to only one carrier network, making them incompatible with multi-carrier SIMs. However, for most other IoT applications using LTE connectivity, multi-carrier SIMs offer the most efficient and reliable connectivity.
Multi-carrier SIMs provide expansive coverage and redundancy in case the primary network fails. When a deployment spans multiple regions, relying on a single carrier often isn’t sufficient since no one carrier can guarantee the best coverage everywhere. For global deployments, multi-carrier SIMs ensure seamless connectivity by accessing various networks.
These SIMs are also used for non-global deployments. Network interruptions happen from time to time, so for IoT devices that require constant connectivity, having access to secondary networks is crucial. Multi-carrier SIMs provide redundant coverage, allowing the device to switch to another network if the primary one goes down.
Additionally, multi-carrier SIMs are a future-proof choice for deployments that aren’t global yet but may scale in the future. They provide flexibility and room to grow, ensuring your IoT devices can adapt to expanding geographical needs.
How does a multi-carrier SIM choose a carrier?
A multi-carrier IoT device uses the settings stored on its SIM, the PLMN (public land mobile network) list, to prioritize which network it connects to. A PLMN is an MNO’s network within a specific country or region. Prioritization of PLMNs is based on factors like signal quality and data costs to maximize reliability and efficiency. When a multi-carrier device is turned on or loses connection, the SIM follows this PLMN selection process to choose the available network with the best signal:
- Is the HPLMN available? The SIM will always try to connect to the Home PLMN first.
- Is the SIM automatic or manual? If the SIM is steering, it will follow the predefined queue of preferred networks. If it’s non-steering, it will automatically choose the network with the strongest signal by continuing through these network selection steps.
- Are there any RPLMNs or EPLMNs? Next, the SIM turns to the Registered PLMN (RPLMN) list, a list of successfully connected PLMNs. It will also search for Equivalent PLMNs (EPLMNs) that carriers have deemed equivalent to an RPLMN.
- Is there an EHPLMN? The HPLMN carrier indicates Equivalent Home PLMNs (EHPLMNs), which are networks from other MNO base stations in areas where they do not have established connection.
- Are there any OPLMNs? If the SIM has been set up with Operator Controlled PLMNs (OPLMNs), it prioritizes these next.
- Which PLMNs have the best signal? Finally, the device searches for any other PLMNs, prioritizing them based on signal strength.
The multi-carrier SIM follows these steps until it finds a PLMN with a signal that’s strong enough to carry out device functions. If the device fails to connect to a network, it adds that PLMN to the Forbidden PLMN (FPLMN) list. This list tells the device which networks should not be considered in the future. Since network reliability changes over time, it’s best to regularly review and reset the FPLMN.
Advantages of multi-carrier SIMs
There are many different types of SIMs, and OEMs are tasked with the challenge of choosing one for their IoT devices. The right SIM will provide reliable connectivity for optimal device functionality, making it vital to the success of your deployment. By understanding both the advantages and limitations of multi-carrier SIMs, you can make an informed decision on whether their capabilities align with your business’s specific IoT project requirements.
Multi-carrier SIMs offer a cost-effective solution for many IoT use cases, especially those connected through LTE technologies. With the ability to switch to the most cost-effective network available, they can help businesses reduce operational costs without compromising on the quality of connection. This flexibility in network selection translates to lower roaming charges, as well as improved regional coverage. When a single carrier can’t offer the best service in every area of deployment, multi-carrier SIMs ensure devices maintain strong and reliable connections.
For businesses operating across different regions, multi-carrier SIMs streamline the onboarding process. By eliminating the need to navigate the complexities of various carrier agreements and network setups for each area, your business can efficiently onboard new customers without complicating internal operations. With a single SIM solution that works across multiple networks, your business can focus time and resources on scaling operations and improving products for increased revenue and customer satisfaction.
Limitations of multi-carrier SIMs
While multi-carrier SIMs are ideal for many IoT applications, they are not suitable for high data Fixed Wireless Access (FWA) and Business Internet applications, which require more robust data transfer capabilities than multi-carrier SIMs can typically provide. However, these two applications are fixed and do not require roaming, making multiple carriers unnecessary except for backup Internet. Additionally, certain technologies like NB-IoT are not compatible with multi-carrier SIMs, limiting use for deployments that use this type of narrowband connectivity.
Another drawback of multi-carrier SIMs is the potential for roaming restrictions in certain geographies or on specific networks. Not all multi-carrier SIMs have permanent roaming rights, which can result in connectivity issues in regions where these rights are not granted. This limitation can vary significantly between connectivity providers, since some offer more capable multi-carrier SIMs with broader roaming agreements than others. Before choosing a multi-carrier SIM, evaluate options from different providers to ensure it will meet your geographical needs.
Zipit’s global roaming SIM provides permanent, extensive connectivity by leveraging pre-established relationships with leading carriers around the world. By avoiding roaming in countries with high roaming costs or permanent roaming restrictions, our solution ensures cost-effective, reliable connectivity and compliance with local regulations. With Zipit’s global SIM, your business can achieve seamless, dependable IoT connectivity across diverse regions.
Manage multi-carrier connectivity with Zipit Wireless
Once you’ve determined a multi-carrier SIM is right for your business’s IoT deployment, the next step is finding a partner that can provide the SIM you need and simplify the management of multi-network connectivity. With over a decade of experience helping OEMs choose and manage connectivity solutions, Zipit Wireless is equipped to help your business do the same.
Zipit offers a variety of steering and non-steering multi-carrier SIMs that support all modern form factors. Whether you need roaming capabilities for a global deployment or redundancy for a mission critical application, we can recommend and provide the right SIM for your business’s use case. No matter which solution you choose, you’ll benefit from our pre-negotiated agreements with excellent rates, significantly reducing your connectivity costs.
By partnering with Zipit, you also gain access to our robust connectivity management platform, enabling you to manage all your SIMs and carrier plans from a single, user-friendly interface. This centralization simplifies the process of monitoring and controlling your connectivity, reducing administrative overhead and ensuring your IoT devices remain consistently connected. The platform also provides real-time device usage insights, which allows businesses to bill customers with a consumption-based pricing model.
Contact Zipit to learn whether multi-carrier SIMs are right for your IoT deployment and how your business can benefit from our cellular connectivity services.
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