An is a digital verification or one-time password (OTP) sent to a mobile device through a global SMS gateway service often associated with the sender ID NXSMS . Businesses use these codes for Two-Factor Authentication (2FA), account registration, and secure login processes. How the NXSMS Service Works

Scammers frequently send unsolicited verification codes to trick users into revealing them. Never share an SMS code with anyone, even if they claim to be from a trusted service.

If you are looking for research on how SMS codes (OTPs) are analyzed or secured, these are the leading recent papers: