In the field of mobile telephony / M2M, network independence means that the SIM card used does not prefer or prescribe the use of a specific mobile network. In this context, steered and non-steeredroaming is also frequently mentioned.
The availability of a mobile network varies depending on location. Sometimes the network of a provider is stronger, sometimes worse. Because of these fluctuations in network availability, so-called M2M SIM cards are used for M2M and IoT projects, which are able to use the mobile networks of different network operators.
These M2M SIM cards are offered by the major network operators themselves, as well as by many other companies that, unlike network operators, do not have their own mobile networks. wherever SIM is one such company. We don't have our own mobile networks, but we have concluded agreements with network operators worldwide that allow our M2M SIM cards to use the networks of these operators.
In theory, devices with M2M SIM cards from network operators are also allowed to use the networks of other network operators. But in practice, this usually only works if the network operator itself no longer offers a signal locally. So if network operator T offers a better network at a location than operator V, the terminal device must use V's network despite poor reception. Only when V really no longer offers reception should the stronger network of T be used.
This case is also referred to as steered roaming: The SIM card prescribes a certain priority for the device when using the network. With our SIM cards, it is not the network operator that counts, but exclusively the strength of the available mobile network at a location. In the above example, our M2M SIMs would have immediately allowed the device to connect to the network of provider T. As soon as V offered a better network than T, the device would automatically be allowed to switch. This possibility of selecting or using the network completely independently of the provider is hidden behind network independence or non-steered roaming.