Modelling public agencies authentication flow against Matrix home server

Problem:

• The eID, Elster and username/ password are key user identification functions for BundID (German and otherwise).
• It is still unclear at which stage of the user account creation and authentication processes for public agencies or public servants managing specialized IT processes the BundID components should communicate with the Matrix BE (including MXID and the Matrix security key).

Goal:

Clarify at which stage of the public agencies or public servants managing specialized IT processes account creation and authentication processes the Matrix components should interact with the BundID-IdP components.

ACs:

• Using a C4 diagram, describe the step-by-step process for creating a user account and logging in with an eID.
• Document the diagram in this ticket and in the solution architecture repo: https://gitlab.opencode.de/fitko/matrix-g2x/solution-architecture

Notes/Resources:

• Requirements uIDs: LB_30