!!! Overview [{$pagename}] is a [token] that is involved in [Access] !! [OAuth 2.0] [{$pagename}] In [OAuth 2.0], [{$pagename}] is a [Token] issued to the [OAuth Client] by the [Authorization Server]. [{$pagename}] is used as a [credential] for the [OAuth Client] when attempting [access] to a [Resource Server] The [Resource Owner] involved in [authorization] decision and grants [Permissions] (via [OAuth Scopes]). * [{$pagename}] has a [Expiration Date], Usually Time limited, but large time. * [{$pagename}] [MAY] be revoked by [Resource Owner] actions * [{$pagename}] Contains [Authorized|Authorizations] via [OAuth Scopes] * [{$pagename}] in [OAuth 2.0] the [Access Token Type] is __MAY NOT__ be specified and then it is a [Bearer Token]). The [OAuth 2.0 Audience Information] add an additional "audience" parameter to the [{$pagename}] You maybe wondering [Why Access Tokens]? !! Contents [{$pagename}] in [OAuth 2.0] the type is not specified other than that the [{$pagename}] is a [Bearer Token]. [{$pagename}] is returned from an in an [Authorization Response] as: {{{ HTTP/1.1 200 OK Content-Type: application/json;charset=UTF-8 Cache-Control: no-store Pragma: no-cache { "access_token":"mF_9.B5f-4.1JqM", "token_type":"Bearer", "expires_in":3600, "refresh_token":"tGzv3JOkF0XG5Qx2TlKWIA" } }}} [{$pagename}] in [OpenID Connect] is specified as a [JSON Web Tokens] the type ([typ]) is specified in the [{$pagename}] %%prettify {{{ { "alg": "RS256", "typ": "JWT" } . { "iss": "https://example.auth0.com/", "aud": "https://api.example.com/calandar/v1/", "sub": "usr_123", "scope": "read write", "iat": 1458785796, "exp": 1458872196 } }}} /% [Access Token Validation] describes how [Validation] SHOULD be performed. !! [OAuth Confidential Client], [OAuth Public Client] and [access Token] [OAuth Confidential Client] [authenticate] to the [Token_endpoint]. and not the [Authorization_endpoint] where as [OAuth Public Clients] obtain [{$pagename}] form the [Authorization_endpoint]. !! [OAuth Parameters Registry] for [{$pagename}] * access_token - [OAuth Parameters Registry] * urn:ietf:params:oauth:token-type:access_token - [Internet Draft] [OAuth 2.0 Token Exchange] !! [MSFT Access Token] [MSFT Access Token] is a [{$pagename}] used in [Microsoft Windows] !! More Information There might be more information for this subject on one of the following: [{ReferringPagesPlugin before='*' after='\n' }]