This document summarizes the various use cases of DI4R. The use cases are categorized by role: whether an entity is a consumer or a producer of attributes.
also compare trust model to federation/eduGAIN
How does verification actually work in IRMA?
https://irma.app/docs/overview/
Any entity that normally relies on an authentication flow that also aggregates attributes may use IRMA or other service for login. In this process, the user is challenged with a QR Code to brandish attributes with the help of the wallet app. The wallet app reads the QR code and engages in user interaction: it shows what is requested by the service and which "cards" - previously stored attributes accommodate the request, if any. Alternatively, in this flow the user may acquire new cards to fulfill the request. The wallet then sends the attributes to the service, which can verify them with an background call.
With this method the Verifier no longer trusts an IdP (something that is exposed on the public internet) but trusts the authentication and the possession to the wallet. Arguably, this provides the opportunity to a stronger level of assurance (i.e. two factors to the wallet+possession of the device).
An obvious source of "cards" is a SAML federation. In order for a SAML attribute of a user to be converted to a card, the user needs to visit an entity that acts as a proxy. This proxy needs to behave as a SAML SP towards the user and the SAML federation. The user needs to visit the site with the intent of adding a card to their IRMA app so that the IRMA infrastructure can store the data as a card. The user will be logged in to this SAML SP which will consume the attributes from an IdP / AA then store it to the IRMA infrastructure.
An authentication source may already have to support multiple protocols, (for instance, SAML and OIDC) in order to cater for the modern web environment. A logical extension of this idea is to support an additional protocol, the card Issuer.
In a traditional SAML flow the following happens. The goal is to enable user Aladár (A) to manage the authorisation of user Béla (B) authorization to service S, but in a way that this information is not maintained in S but in an external source, the Membership Management Service (MMS).
With the introduction of DI4R, the flow may be significantly simplified.
With this solution B does not have to use the same login (i.e. the MMS and the target S do not need to be in the same federation). Possibly, B can receive the card at a page maintained by the DI4R provider.
Or, perhaps the DI4R provider's web interface serves as a landing page for the invitation?
https://irma.app/docs/revocation/