Internet Engineering Task Force (IETF) D. M'Raihi Request for Comments: 6238 Verisign, Inc. Category: Informational S. Machani ISSN: 2070-1721 Diversinet Corp. M. Pei Symantec J. Rydell Portwise, Inc. May 2011 TOTP: Time-Based One-Time Password Algorithm Abstract This document describes an extension of the One-Time Password (OTP) algorithm, namely the HMAC-based One-Time Password (HOTP) algorithm,
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