Predicate examples

Age Verification for Restricted Content

Verifies that the client is legally old enough to access age-restricted content without revealing their exact age. In the example, client should be older than 18.

• Attribute Type: Date (Date of Birth);

• Predicate: “Date of Birth“ <= “Interaction date minus 6574 days” (6574 days = 18 years);

• Proof Process: The predicate is set upon the “Date of Birth” attribute in the required credential for the interaction. If the client’s credential data meets the condition (client is 18 years or older), the interaction can be executed. If the data in the client's credential does not meet the requirements, the client cannot proceed with the interaction;

Number-based Qualification

Determines if a client's score meets the minimum (85) threshold for qualification without revealing the exact score.

• Attribute Type: Number (Employee Score);

• Predicate “Score“ >= 85;

• Proof Process: The predicate is set upon the “Score” attribute in the required credential for the interaction. If the client's credential data meets the condition (i.e., an employee score of 85 or higher), the interaction can proceed. If the data does not meet these requirements, the client will be unable to proceed with the interaction;

Membership Duration

Confirms that a client has held member since before May 22, 2023, without showing the exact start date of membership.

Attribute Type: Date (Membership Issue Date);

Predicate: Membership Issue Date <= 2023-05-22;

Proof Process: The predicate is set upon the “Membership Issue Date” attribute in the required credential for the interaction. If the client's credential data meets the condition (i.e., the Membership Issue Date is 22/May/2023 or earlier), the interaction can proceed. If the data does not meet these requirements, the client will be unable to proceed with the interaction;

Enum-based Access Control

Verifies if a client holds a “Gold“ level membership to grant access to specific services, while keeping other membership details confidential.

Attribute Type: Enum (Membership Type);

Predicate: Membership Type = “Gold“;

Proof Process: The predicate is set upon the “Membership Type” attribute in the required credential for the interaction. If the client's credential data meets the condition (i.e., the Membership Type is “Gold“), the interaction can proceed. If the data does not meet these requirements, the client will be unable to proceed with the interaction;