Method and apparatus for distributed, privacy-preserving and integrity-preserving exchange, inventory and order book

Method according to the previous claim, wherein the comparing function, “F-compare”, comprises:

• each trader device uses the MPC module to generate the input encoding of private parameters including its own old inventory flags in the previous round, its own new inventory flags in the current round, and the private random numbers from the random generator module;
• each trader device broadcasts the input encoding so computed to the other trader devices using the network module;
• each receiving trader device uses the MPC module to compute an encoded output based on the public input and the received encoded inputs;
• each receiving trader device uses the network module to send the encoded output to the network module of other trader devices;
• each receiving trader device uses the MPC module to:
• check whether all other traders devices' respective private old inventory flags in the previous round, new inventory flags in the current round, correspond the public input commitments of old inventory flags in the previous round and new inventory flags in the current round, and return 0 if at least one check fails;
• compute the sum across all trader devices of all mentioned private new flags and the sum across all trader devices of all mentioned private old flags and returning 0 if the two sums are different;
• return 1 if no value has been already returned.