Method and system for time-sequential authentication of shipments in supply chains

Abstract

In one embodiment of the present invention, a source point, or security management entity, within a supply chain labels a shipment to be shipped through the supply chain with numbers, text strings, or other type of label information. Different label information may be placed at each of multiple levels of packaging as well as on objects within the packaging. The source point devises an encryption-key chain via a one-way function, and encrypts combinations of the label information incorporated within the packaging and objects using encryption keys from the encryption-key chain to produce one or more encrypted label tags. The one or more encrypted label tags are affixed to the shipment by the source point, and the shipment is sent into the supply chain for eventual delivery to a destination point. At pre-selected intervals of time, the source point reveals encryption keys within the encryption-key chain. In one embodiment of the present invention, revealing of encryption keys allows intermediate points or the destination point in the supply chain at which the shipment resides to extract label information and apply the most recently revealed encryption key to compute a label-tag value, and to then compare the computed label-tag value to a label tag affixed to, or incorporated within, the shipment.