Patent ID: 8185744

Claim:
A method for generating an aggregate digital signature, said method comprising: obtaining, by a computing device, a first signature, said first signature comprising: a first signature component which has been generated by encrypting a first portion of data using a first encryption key; and a second signature component, said second signature component having been generated from a first intermediate signature component and a first private key, said first intermediate signature component having been generated from said first signature component and a second portion of data; generating a third signature component by encrypting one of said first and second signature components using a second encryption key in the same manner as said first signature component encrypts said first portion of data; generating a second intermediate signature component from said third signature component and said second portion of data; generating a fourth signature component from said second intermediate signature component and a second private key; outputting a second signature as said aggregate digital signature, said second signature comprising the other of said first and second signature components, and said third and fourth signature components; and wherein said computing device is in communication with a radio frequency identification (RFID) device, said RFID device configured to at least one of read and write an RFID tag.