Will there be just one type of EPC?
No. The Auto-ID Center originally proposed EPCs of 64-, 96- and 128-bits. Eventually, there could be more. The 96-bit number is the one the center believed would be most common. It chose 96 bits as a compromise between the desire to ensure that all objects have a unique EPC and the need to keep the cost of the tag down (the less information on the microchip the cheaper the cost of producing the chip). The 96-bit EPC provides unique identifiers for 268 million companies. Each manufacturer can have 16 million object classes and 68 billion serial numbers in each class, more than enough to cover all products manufactured worldwide for years to come. Since there is no need for that many serial numbers at this time, the center has proposed an interim 64-bit code. The smaller code will help keep the price of the RFID chips down initially (the simpler the chip, the cheaper the tag), while providing more than enough unique EPCs for current needs. The center foresees using a 128-bit code to cover all the items made around the world.
