GSM modems with KPN SIM cards that transfer data over the 2G network via dialled connections will no longer function as of 1 April 2021. Examples of such GSM modems are
Severa GSM modems
GSM versions of Octalarm-T and Octalarm-IP alarm detectors for pagers
When data transfer is still required, such modems should be replaced by GSM modems and alarm detectors with internet-based data transfer based on GPRS, 3G or 4G. Because the 2G and 3G networks are also switched off, 4G modems are preferred.
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