As small as the head of a pin, T-Mobile new subscriber identity module (SIM) cards aren’t designed for any mobile phone you’d buy in its stores. Instead, these SIMs will embedded into telematics modules, where they will mounted into smart meters and other M2M devices around the country.
The embedded SIMs aren’t just tinier, they’re more durable, built from silicon rather than plastic, and designed to hard-wired into devices in the factory. Instead of manually provisioning each device, a supplier can ship the M2M modules directly to the field where they can be installed and activated–a big plus, considering smart grids could support millions of nodes. While each module might only be expected to transmit a few kilobytes of information every month over T-Mobile’s GSM/EDGE network, many of them will be sitting outdoors, exposed to the environment, so durability counts.
T-Mobile’s first customer for the embedded SIMs will be Echelon, which will embed the T-Mobile SIMs into its cellular-radio-fed smart meters, which will be deployed on electrical grids throughout the US.