card bank -- equipment with a large number of ic card connectors and sim card connectors

There is a device that needs a large number of ic card connectors and sim card connectors, which is called card bank.

The role of card banks is to send messages in groups. There are generally 256 card banks and 512 card banks.

A device has 256 sim card connectors, which can operate 256 sim cards at the same time to execute instructions.

The instructions are generally mass SMS messages, which can also be used by mobile operators as account opening activation of batch sim cards,

and keep sim cards online. Similarly, the sim card can also be replaced with an ic card, which requires 256 ic card connectors.