When designing for IoT, please consider:

Equipment: Equipment and deployment features will affect the choice of mobile network connection. Factors to consider include the lifespan of the equipment and the power required to maintain deployment. Large scale deployment in remote, global, or vast locations requires consistent power sources as they may remain in place for extended periods of time.

Data: What type and quantity of data does the device need to exchange? It may only send small packets, or it may require higher bandwidth to exchange videos. It is best to consider how device applications evolve over time, such as from sending audio files to adding videos. Regardless of the amount and type of data, connections must be secure, as large-scale IoT deployments present a large attack surface with ongoing risks. Therefore, please consider the value of data and multi network resilience.

• Distribution: Distribution is a key consideration as network options and commercial arrangements for national, regional, and international deployments may vary. It is always best to set a stock keeping unit (SKU) for devices, but this may not be possible if devices shipped to different markets have different SIM cards. In this case, when the device reaches its target for later connection, it may be necessary to add a region specific SIM.

• Coverage: This involves wireless technology used to connect devices. Low power wide area networks (LPWAN) (NB IoT and LTE-M) are popular, but their global coverage is insufficient, and there are even gaps at the national level. Ensure that your device will definitely cover and that you do not have the opportunity to deploy to countries/regions without LPWAN at all. As is well known, the UK offers LTE-M on the east side and NB IoT on the west side. There are also many similar coverage gaps around the world, and even developed countries like Brazil cannot provide consistent LPWAN coverage.

• Gradually phasing out 2G and 3G

• A large number of IoT applications aim to connect through 2G and 3G. These networks are gradually being phased out, and as far as 3G is concerned, many regions have already closed or are planning to close in the near future. The main reason is that mobile network operators (MNOs) hope to release spectrum for next-generation, cost-effective, and higher revenue generating technologies.

Most companies that deploy IoT through 3G connections will enter their migration plans. 2G is slightly different because it is a technology deeply rooted in the large-scale deployment of machine to machine (M2M) and IoT connected devices, especially in Europe, so there are indications that in many countries, 2G will not stop until at least the end of this century. Although this may seem distant, forward-looking planning is crucial for deploying devices for many years.

There are a series of 2G/3G connection alternatives, each with its own features. These should be weighed to evaluate whether they are suitable for the new IoT devices in the design:

NB - Internet of Things

This is most suitable for fixed IoT devices that send small amounts of non real time data, powered by batteries or solar energy, and located in areas where other technologies find it difficult to obtain signals. NB IoT provides low hardware and operational costs, making long-term large-scale deployment feasible. It has battery efficiency, so it can support devices that stay on site for long periods of time, such as sensors with low and intermittent data throughput. NB IoT has strong signal penetration and is actually the deepest coverage range in any low LPWAN, so if sensors or water meters are deployed below the street, it can handle basements or underground parking lots.

LTE-M （Cat-M1）： This provides the highest throughput speed and bandwidth among any LPWAN technology, allowing it to handle wireless (OTA) updates such as firmware or network operator profiles. It provides latency and speed roughly equivalent to 3G, with high battery efficiency and cost-effectiveness.

LTE-M (Cat-M1) can support a wide range of IoT applications, but is very suitable for low-power devices that require higher speeds or bidirectional data transmission, such as devices that support voice or SMS services. It can be used by both mobile and fixed devices as it supports unit to unit roaming.

However, due to coverage reasons already mentioned, some deployments will be difficult to use NB IoT or LTE-M. NB IoT and LTE-M are both unavailable on 4G, and NB IoT is currently incompatible with eSIM.

If these restrictions make LPWAN unsuitable, the company may consider:

• LTE Cat-1 and Cat-1 BIS: LTE Cat-1 (Cat-1 BIS is a single antenna version) is a mature technology. The hardware cost and power consumption are slightly higher than LTE-M and NB IoT, but for some deployments, the benefits will outweigh this. It has global support because Cat-1 is a standard 4G technology, and the existing roaming protocol means that global networks can be accessed through a single SIM SKU. It is suitable for mobile applications and compatible with eSIM.

• The lower latency and higher bandwidth make Cat-1 a powerful alternative to 2G/3G and can support a wide range of IoT applications. For low-power IoT devices that require higher speeds, consideration should be given to using bidirectional data transmission or mobility, and applications that can support a battery life of three to five years or use rechargeable batteries.

• Electronic touch for flexible connectivity

• ESIM is an ideal technology for achieving flexibility as it supports OTA configuration of network operator credentials. This means that the same SIM card can be inserted into every device, no matter where they are going, as connections can be configured in the future. This provides a single SKU that is crucial for operational simplicity, especially for large-scale international IoT deployments. This makes the manufacturing process simpler and more streamlined, and connectivity allows for the use of local networks at local rates.

• In addition, eSIM makes it possible to change network operators in daily life without physically replacing SIM cards. In this way, the company can utilize new business arrangements and attractive transactions. When designing IoT devices with cellular connectivity, a series of considerations need to be taken into account. The devices themselves, the data they will exchange, and their target geographic location will all play a role in determining the correct cellular connection selection.

• Network technology is not forever, as companies that have completed or are in the process of migrating from 2G and 3G will know, so the lifecycle of technical standards is another factor that needs to be kept in mind. The benefit of certain technologies lies in their flexibility - eSIM brings agility to IoT deployment in the right place. In summary, IoT connectivity platform providers will be able to provide optimal cellular connectivity recommendations for each specific IoT use case.