A handful cryptographers were asked for feedback on the architecture of the European Identity Wallet (the Architecture Reference Framwork (ARF), currently at version 1.4.0). We seized the opportunity to write a short report to urge Europe to reconsider the design, and to base it on the use of anonymous (aka attribute-based) credentials.

Anonymous credentials were designed specifically to achieve authentication and identification that are both secure and privacy-preserving. As a result, they fully meet the requirements put forth in the eiDAS 2.0 regulation. (The current design does not.) Moreover, they are by now a mature technology. In particular we recommend to use the BBS family of anonymous credentials, which are efficient and mathematically proven secure.