Patent ID: 8688940

Claim:
A method for using a â€œCompletely Automated Public Turing Test to Tell Computers and Humans Apartâ€ (â€œCAPTCHAâ€) challenge to protect a removable mobile flash memory storage device, the method comprising: performing by a removable mobile flash memory storage device in communication with a host device, wherein the removable mobile flash memory storage device lacks a physical write-protect switch movable by a user between a first position that allows writes to the removable mobile flash memory storage device and a second position that prevents writes to the removable mobile flash memory storage device: receiving a command from the host device; determining if the command is a restricted command, wherein a restricted command is a command that would not be performed if a write-protect switch were present on the removable mobile flash memory storage device and in the second position; only if the command is a restricted command: generating a CAPTCHA challenge; providing the CAPTCHA challenge to the host device; receiving a response to the CAPTCHA challenge from the host device; determining if the response satisfies the CAPTCHA challenge; and performing the command only if the response satisfies the CAPTCHA challenge; wherein the CAPTCHA challenge is provided to the host device on a command-by-command basis only if it is determined that the command is a restricted command, and wherein the CAPTCHA challenge is a substitute for having a write-protect switch on the removable mobile flash memory storage device.