US 11,966,912 B2
System and method for cryptographic-chain-based verification of postage transaction records
Yang Lu, Los Angeles, CA (US); and Michael Biswas, Culver City, CA (US)
Assigned to AUCTANE, INC., Austin, TX (US)
Filed by Stamps.com Inc., EL Segundo, CA (US)
Filed on Jun. 26, 2017, as Appl. No. 15/633,692.
Prior Publication US 2018/0374087 A1, Dec. 27, 2018
Int. Cl. G06Q 20/38 (2012.01)
CPC G06Q 20/382 (2013.01) [G06Q 20/38215 (2013.01); G06Q 20/3823 (2013.01); G06Q 20/3825 (2013.01); G06Q 2250/05 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method of facilitating cryptographic-chain-based verification of postage transaction records, the method being implemented by a customer computer system associated with a customer of a postage vendor, the customer computer system comprising one or more processors executing computer program instructions that, when executed, perform the method, the method comprising:
obtaining a customer private key associated with the customer from a secure local storage at the customer computer system;
obtaining a first vendor digital signature derived from a first postage transaction record, the first postage transaction record relating to a previously executed transaction;
responsive to a purchase request, completing a current purchase transaction for a product associated with the postage vendor and storing information associated with the purchase transaction as at least part of a second postage transaction record, the completing being performed without communicating with a vendor computer system;
creating a customer digital signature using (i) the customer private key, (ii) the first vendor digital signature, and (iii) the second postage transaction record;
providing validation of the completed current purchase transaction to the vendor computer system associated with the postage vendor by transmitting the customer digital signature to the vendor computer system;
responsive to transmitting the customer digital signature, obtaining a second vendor digital signature from the vendor computer system, the second vendor digital signature being different from the first vendor digital signature and being created using (i) a vendor private key associated with the postage vendor and (ii) the customer digital signature; and
storing the second vendor digital signature to be used in a subsequent transaction.