Open ID
OpenID is an open standard and decentralized authentication .
Promoted by the non-profit OpenID Foundation, it allows users to be authenticated by co-operating sites (known as Relying Parties or RP) using a third party service, eliminating the need for webmasters to provide their own ad hoc login systems, and allowing users to log into multiple unrelated websites without having to have a separate identity and password for each.
Users create accounts by selecting an OpenID identity provider, and then use those accounts to sign onto any website which accepts OpenID authentication. Several large organizations either issue or accept OpenIDs on their websites according to the OpenID Foundation:
The OpenID standard provides a framework for the communication that must take place between the identity provider and the OpenID acceptor (the "relying party"). An extension to the standard (the OpenID Attribute Exchange) facilitates the transfer of user attributes, such as name and gender, from the OpenID identity provider to the relying party (each relying party may request a different set of attributes, depending on its requirements).
The OpenID protocol does not rely on a central authority to authenticate a user's identity. Moreover, neither services nor the OpenID standard may mandate a specific means by which to authenticate users, allowing for approaches ranging from the common (such as passwords) to the novel (such as smart cards or biometrics).
The term OpenID may also refer to an identifier as specified in the OpenID standard; these identifiers take the form of a unique Uniform Resource Identifier (URI), and are managed by some 'OpenID provider' that handles authentication.
The current version of OpenID is OpenID Connect 1.0, finalized and published in February 2014, and updated with corrections in November 2014.
As of March 2016[update], there are over 1 billion OpenID enabled accounts on the Internet (see below) and approximately 1,100,934 sites have integrated OpenID consumer support.
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