Re: [GNAP] [Txauth] Revisiting the photo sharing example (a driving use case for the creation of OAuth)

Justin Richer <> Thu, 13 August 2020 15:15 UTC

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From: Justin Richer <>
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Date: Thu, 13 Aug 2020 11:15:27 -0400
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Subject: Re: [GNAP] [Txauth] Revisiting the photo sharing example (a driving use case for the creation of OAuth)
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Denis, I want to focus on one point here:

> In OAuth 2.0, the user consent is performed by the AS using an authorize endpoint where the user consent is solicited and captured.
> Since a user, with no prior experience, shall first connect to a RS to perform an operation, the user consent shall be performed by the RS, 
> instead of the AS. This means that we should define a "consent" endpoint at the RS.

One of my goals with XYZ’s design was to be able to separate the interaction with the user from the web-based flows for the delegation protocol, and that aspect is enshrined in the GNAP charter as well.

It points to the reality that there are two different aspects of the traditional AS that we might need to talk about separately now. One deals with delegation, issuing tokens, returning data directly to the client (not through a separate API, since that’s the RS), and other back-channel stuff. The other aspect deals with interacting with the user and/or resource owner. 

We already saw bits of this in OAuth 2: the AS is defined by the pair of the token endpoint and authorization endpoint, each filling the respective roles above. What if we formally separate these? Strawman names:

Delegation Server (DS) - handles the back-channel stuff

Interaction Server (IS) - handles the front-channel stuff

 — Justin