ADT in the US already did this, funny enough. They acquired a company called CellBounce (https://cellbounce.com/ https://cellbounce.com/) that manufactures a v

ADT in the US already did this, funny enough. They acquired a company called CellBounce (https://cellbounce.com/ https://cellbounce.com/) that manufactures a very small 3G-LTE gateway. They bind it to a single device (eg, locking it to an alarm panel's IMSI) and pass the authentication through to AT&T to allow the panel onto the LTE network. Most of the device itself is just a giant lead acid battery, and the actual CellBounce motherboard is... actually very low component count and tiny. The actual Qualcomm femtocell board (linked below) that they built as a reference design for the chipset is... amazingly tiny. https://fccid.io/2AUQ4-CB34U/ https://fccid.io/2AUQ4-CB34U/ https://old.hotchips.org/wp-content/uploads/hc_archives/hc24/HC24-7-SOC/HC24.29.725-FSM-Femtocell-Blessent-Qualcomm.pdf https://old.hotchips.org/wp-content/uploads/hc_archives/hc24...