Patent ID: 7512236

Claim:
A method for secure mobile commerce within a mobile commerce system having a pre-defined communications protocol, the mobile commerce system including a plurality of readers and a plurality of transponders, the plurality of transponders including first transponders having an unencrypted communications format and second transponders having an encrypted communications format, the method comprising the steps of: transmitting a trigger signal from one of said plurality of readers; receiving a response signal from one of said transponders; testing said response signal to determine whether said response signal is from one of said first transponders or one of said second transponders; engaging in unencrypted communications with said one of said transponders in accordance with the unencrypted communications format if said response signal was received from one of said first transponders; and engaging in encrypted communications with said one of said transponders in accordance with the encrypted communications format if said response signal was received from one of said second transponders.