So, Smart cards are easy... but not foolproof. You need a hybrid solution. Security is based mostly on psychology of the target market. Like they say NOTHING is unbreakable. I was part of the team that built the 64bit encryption for credit a card in 1994. I have over 25 years experience in technology - Electronics, IT/Programming, Hardware, Databases, RF/GSM/VOIP, etc. What I can do is do you a feasibility - pros and cons on the various methods as the 1st stage and the 2nd stage can be to develop the prototype of the selected method. The budget I have specified is 'indicative' only. I am a Canadian Technology business and work strictly with an advance/confirmation fee of a minimum of 25%.