Credit Card Numbers - Visa. These Credit card numbers validate for Visa credit cards. The number and information is as real as it can be, and contains valid bin information. The structure of the credit card number starts with a valid bin number and also validates against the LUHN's formula.
UART is a protocol (Universal asynchronous receiver/transmitter ) for serial transfer of information. You ask about an embedded system with mentioning which so I'll assume that you have a block diagram with one indicating UART.
SMS is generally used to inventory devices and to make updates to operating system and applications. Complex WBT implementations frequently use SMS in combination with Microsoft Internet Explorer and line-of-business applications. SMS is especially helpful in this implementation for inventory and update management.