ntegrated SIM (iSIM) looks like being not just the next generation, but the end game, for cellular device authentication. It is gaining traction already in the IoT, for small devices that cannot accommodate even a dedicated embedded SIM (eSIM) chip, never mind a physical SIM. But it will take longer to displace the eSIM in larger form factors. In iSIM, all SIM functions are integrated into the device system-on-chip (SoC). That represents a next step from the eSIM, which was itself inspired partly by the increasing desirability of saving onboard space in the smartphone. It can reduce the SIM footprint about threefold, to 6mm x 5mm, compared to the nanoSIM at 12.3mm x 8.8mm, which itself had evolved to be…