Zero-knowledge interaction processing system and method

A user device comprising:

• a processor;
• and
• a computer-readable medium coupled to the processor, the computer-readable medium comprising code executable by the processor for implementing a method comprising:
• generating an initiate interaction request message comprising a state commitment;
• providing the initiate interaction request message to a first server computer, wherein the first server computer creates an verify state request message comprising an interaction index, an interaction index commitment, and a first commitment signature formed from the state commitment and the interaction index commitment;
• receiving the verify state request message from the first server computer;
• generating a modified verify state request message comprising a user device public key, the state commitment, the interaction index commitment, and the first commitment signature;
• providing the modified verify state request message to a second server computer, wherein the second server computer verifies the state commitment, verifies the first commitment signature, and creates a second commitment signature formed from the state commitment and the interaction index commitment;
• and
• receiving a verify state response message comprising the second commitment signature from the second server computer.

A method comprising:

• receiving, by a first server computer, an initiate interaction request message from a user device, wherein the initiate interaction request message comprises a state commitment, which requests an interaction be processed;
• determining, by the first server computer, an interaction index for the interaction;
• generating, by the first server computer, an interaction index commitment based on the interaction index and a random value;
• generating, by the first server computer, a first commitment signature by signing a combination of the interaction index commitment and the state commitment using a first server computer private key;
• creating, by the first server computer, a verify state request comprising the interaction index, the random value, the interaction index commitment, and the first commitment signature;
• and
• providing, by the first server computer, the verify state request to the user device.