An Application of a Group Signature Scheme with Backward Unlinkability to Biometric Identity Management

We introduce a new identity management process in a setting where users’ identities are credentials for anonymous authentications. Considering identity domains organized in a tree structure, where applying for a new identity requires to previously own the parent identity, we enable a cascade revocation process that takes into account this structure while ensuring anonymity for non-revoked users, in particular, towards the providers of other identity domains. Our construction is based on the group signature scheme of (Bringer and Patey, 2012).