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OAuth 1.0 emerged from the large social providers like Facebook, Yahoo!, AOL, and Google. Each had developed its own alternative to the password anti-pattern. OAuth 1.0 reflected their agreement on a single community standard. As a result of security upgrades, OAuth 1.0a was released as the revised specification that offered upgraded security to users. In 2009, recognizing the value of more formalized standardization, that community contributed OAuth 1.0 to the IETF. It was within the IETF Working Group that the original OAuth 1.0 was reworked and clarified to become the Informative RFC 5849.
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After more standardization, in 2010, Microsoft, Yahoo!, and Google created the Web Resource Authentication Protocol (WRAP), which was soon submitted into the IETF WG as input for OAuth 2.0. WRAP proposed significant reworking of the OAuth 1.0a model. Among the changes were the deprecation of message signatures in favor of SSL, and a formal separation between the roles of ‘token issuance’ and ‘token reliance.’
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