The context is the US mobile drivers licenses and the forthcoming digital identity documents in the EU. The government gives you an electronic document stored in your device, and now the problem is, why would you ever want to give a copy of your document to a third party.
This code solves the problem via zero-knowledge presentations of the document. This is real stuff already integrated in Google Wallet, not vaporware. See also the paper linked from GitHub.
Ignore the marketing in TFA.
The paper linked from Github is at [1]. Section 6.1 gives a fairly practical example of use with a passport, while 6.2 talks about how it might be used with a drivers license.
How do you prevent kids just obtaining a copy of such electronic document from somewhere? The actual document itself doesn't prove anything about your age; it just proves that you have the document.
The context is the US mobile drivers licenses and the forthcoming digital identity documents in the EU. The government gives you an electronic document stored in your device, and now the problem is, why would you ever want to give a copy of your document to a third party. This code solves the problem via zero-knowledge presentations of the document. This is real stuff already integrated in Google Wallet, not vaporware. See also the paper linked from GitHub. Ignore the marketing in TFA.