What is Identity Mixer?

These pages are outdated.  Please go to www.zurich.ibm.com/idemix for the most recent information or try the installation-free web demo.

Identity Mixer (idemix) is an anonymous credential system developed at IBM Research that enables strong authentication and privacy at the same time.

A credential is a means to establish a claimed identity, roles, or attributes about oneself with an entity, typically as part of an access control request. So for instance an identity card can serve as a credential to establish that one is between 12 and 15 years old as might be required to access a teenage chat. Using a traditional identity card, this would also reveal to the chat side all the other information on the card.

Anonymous credentials overcome this: with such credential a user can selectively reveal any of the attributes contained in the credential without revealing any of their information whatsoever. Thus, anonymous credentials are a key ingredient to protect one’s privacy in an electronic world.


With identity mixer, users can obtain from an issuer a credential containing all the information the issuer is ready to attest about them. When a user later wants to prove to a service provider a statement about her, she employs identity mixer to securely transform the issued credential. The transformed credential will only contain the subset of the attested information that she is willing to disclose. The user can apply this transformation as many times as she wants and still none of credentials can linked to each other.



The postings on this site are personal and don’t necessarily represent IBM’s positions, strategies or opinions.