Eligibility Verification based on Immutable Personal Information without Revealing the Owner’s Identity

When an individual needs to prove eligibility, it is sufficient to know whether or not s/he meets the eligibility, but any existing method inevitably exposes the identity of the owner or unnecessary additional information in the process of providing personal information. In this paper, among the immutable items of personal information such as gender, date of birth, and place of birth, we propose a method in which the owner provides only essential item(s) to the eligibility verifier with each iterm marked on one option among multiple choices. In this way, the eligibility verifier can access the combination of items stored in the blockchain with the consent of the information owner, and can safely store the access history by requesting recording in the blockchain again. In the proposed method, the user does not worry about his/her identity being revealed or his/her personal information being overly exposed, and the eligibility verifier can check only necessary items and search later records without separately storing the records.