Unique User-Generated Digital Pseudonyms

This paper presents a method to generate unique and nevertheless highly random pseudonyms in a distributed environment. More precisely, each user can now generate his pseudonym locally in his personal security environment, e.g. in his smart card or his personal digital assistant. There is no need for any information interchange between issuing parties or global data (especially keys), except unique identifiers for each user and each device of the system. Additionally the holder can prove, that he generated a specific pseudonym without revealing his identity and he can reveal his identity by disclosing the pseudonym. Whereas the verifier of a disclosed pseudonym can be sure, that the presenter of the pseudonym is the holder of the pseudonym (i.e. the person which originally generated it). The identifier of the user and the identifier of the user’s device will be used to generate unique pseudonyms, but to ensure pseudonymity, both components will be stored in the pseudonym in encrypted form.