Patent ID: 9121119
Filing Date: 2015-09-01
Classification: D04H,G06F,G11B

Abstract:
1. A method for monitoring replaceable portions of a device, each replaceable portion having a respective unique identifier associated therewith, said method comprising: said device obtaining from a new portion, a partial list of revoked unique identifiers and a digital signature stored thereon, said partial list having been chosen from a master list of revoked unique identifiers, wherein said digital signature is generated by digitally signing a combination of said partial list and said respective unique identifier associated with said new portion, and wherein said digital signature binds said partial list to said new portion; said device verifying said digital signature; and if said digital signature is verified, said device comparing said respective unique identifier associated with said new portion with identifiers in a locally stored list of revoked identifiers and with identifiers in said partial list, and rejecting incorporation of said new portion if said comparing reveals a match.