Describe creation of Matrix account in the BundID registration flow

Problem

• Synapse is required to provide Matrix accounts for BundID users.
• A Matrix account must be created at latest when accessing Matrix for the first time, e.g. the web client or iOS client we are developing.
• At which step in the username/password registration flow at BundID should a Matrix account be created?
• We need to consider existing BundID accounts (that are/are not linked to a Matrix account) and new BundID accounts.
• How do we deal with upgrading from postal to digital communication (initial communication from Fachbehörde to user took place via postal mail)?

Goal

Define at which step in the username/password registration flow should a Matrix account be created.

ACs

• Describe current BundID registration flow for username/password.
• The approach works for existing BundID accounts.
• The approach works for newly registerd BundID accounts.
• Define at which step will a Matrix account be created.
• Define next steps.
• Document results in this ticket.

Notes/ resources

• Requirement uIDs: LB_178

• See authentication process in #36
• Current state of the discussion:

Business process (see Nextcloud)

Who needs to be involved / informed

• reviewers:
• involved:
• informed: