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The v2.0 standard includes a decoupled authorisation flow, which provides a more customer and mobile friendly option for the customer to authorise consent (that has already been agreed between a customer and Third Party) with the API Provider. This does not replace the existing redirect model summarised below, but instead adds an additional implementation option.
Update for v2.2 (June 2022)
In v2.2 of the API Standards, the Decoupled Flow mechanism has been phased from Optional to Mandatory. This means that an API Provider supporting any version of the Standards after v2.2 must support the decoupled authentication flow function as summarised below and defined in the API Standard.
Redirect authentication flow
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The introduction of decoupled flow in the v2.0 standard opens up a range of new use cases. For example:
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