User Apps with Identifiers

Full Title

This article addresses the various solutions to creation of a synchronized Identifier between a user app and a Relying Party

Context

The example addressed here is a Smartphone app that is uses to establish a user's identifier with a Website over the internet.

Problems

1. The user needs to trust that the app will honor the user's wishes.
2. The web site needs to trust that the app correctly informs it of the user's preferred identifier with:
   1. the appropriate Identity Assurance Level (IAL) aka identity proofing.
   2. the appropriate Authentication Assurance Level (AAL) aka proof of presence and control by the user.
   3. the appropriate Federation Assurance Level (FAL) aka follows the federation rule and regulations. (optional)

Solutions

Two major category of app are consider along with a hybrid that lies between the two.

Native App Solutions

• The app is loaded from a trusted app store and has full access to the features of the device.
• If the smart phone browser is available, (the assumption is that) it will be able to start the app.

=Unsolved Problem

The redirection code (e.g. openid://) can be registered, or hijacked) by any app that the user downloads.

Web App Solutions

• The app is loaded from a trusted web site and has access to the service broker features in the DOM.
• The user on a web browser can be redirected to get a token from the web site, which the browser redirects to the web app.
• Also known as a Progressive Web App or PWA.
• The app is only available when running on a smartphone, but the web address will respond if the if app is not running.

Hybrid App Solutions

• The app works with a website that can present information about user choices at all times.
• For an example, in the solid project, a user stores personal data in "pods" (personal online data stores) hosted wherever the user desires.