Anyone who has dealt with wireless M2M communication knows the advantages of mobile radio for IoT projects. All that's missing is the right M2M SIM card to transmit data quickly and securely from IoT devices. In this article, we explain what you should look for when choosing an M2M SIM provider and where pitfalls lurk for your project.
Whether you need just 15 M2M SIMs or 50,000 SIMs, the following questions and points can help you define important requirements for your future provider of M2M SIM cards.
An M2M SIM uses the networks of different network operators. For this purpose, it is permanently in roaming, also called national roaming. This in turn is divided into steered and non-steeredroaming. Whereas with non-steered roaming the M2M SIM always enables connection to the strongest network available at a location, with steered roaming the network provider decides on the connection. An M2M SIM with steered roaming will always first establish the connection via its home network before using the network of another mobile network provider. However, this may mean that end devices have to make do for a while with a poorer connection than would be possible with another network.
For your application, check whether you can cope with a weak connection and possibly more frequent disconnections in case of doubt. This could be the case, for example, if only very small, non-time-critical amounts of data need to be transferred. If you are dependent on a permanently available and stable connection for your project, an M2M SIM provider with non-steered roaming is more advisable.
Depending on the SIM provider, there are different M2M data tariffs for your IoT project, from a fixed monthly data package per M2M SIM to a shared data pool for all SIM cards. There is no right or wrong tariff model - either it fits your project, or it doesn't. In order to find the right M2M data tariff, you should first ask yourself a few questions about your data requirements:
Do you know the monthly data requirements of your IoT devices, exactly or at least approximately?
If not, look for a provider where you can extensively test the M2M SIM cards in advance. For valid data, a test phase of three to six months is recommended.
Is the monthly data requirement rather constant, or are (strong) fluctuations to be expected?
If data consumption is constant, you can book a fixed data package to match. If data consumption fluctuates, there are pay-as-you-go tariffs, for example, where you only pay for the actual data consumption.
Is your M2M project subject to seasonal peculiarities, so that months without data consumption are expected, for example?
In this case, look for providers who allow you to pause the SIM cards temporarily without additional costs.
Do you expect similar consumption for all M2M SIM cards used, or does consumption vary from card to card? With some M2M SIM providers, you can assign a common data pool to M2M SIM cards. This way, the lower consumption of one SIM offsets the excess consumption of another SIM.
Depending on your answers, you should be able to identify the appropriate data model for your project. This can be a fixed monthly data quota per SIM, as well as a shared data pool for all active M2M SIM cards.
Low acquisition costs quickly become unattractive when monthly fees or hidden costs for M2M SIM cards have to be taken into account. Therefore, check exactly which running costs are incurred for the SIM cards. This refers not only to the data, but also to the M2M SIMs themselves. An unpleasant but not uncommon cost trap: forced activ ations or multiple activation fees.
In the case of forced activations, all purchased M2M SIM cards are activated after a set period of time. From then on, monthly basic fees are usually due for these SIM cards - regardless of whether they are used in an IoT device or are in storage. With multiple activation fees, you can pause SIM cards temporarily and thus save on the basic fee, but pay a fixed amount again each time after reactivation. Both cost blocks can quickly make low one-off costs unattractive.
