= One Time Password =
 * http://www.ietf.org/rfc/rfc4226.txt - HOTP: An HMAC-Based One-Time Password Algorithm

== Mostly open implementations. ==


 * http://motp.sourceforge.net/
 * http://code.google.com/p/google-authenticator/
   * implementations support the HMAC-Based One-time Password (HOTP) algorithm specified in RFC 4226 and the Time-based One-time Password (TOTP) algorithm

== Problems and Concerns with OTP on mobile phone ==
 * http://www.dotnetnoob.com/2011/02/steal-google-account-and-get-free-otp.html


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CategorySecurity