Security is at the forefront of many applications, and several Flash products are now equipped with two 64-bit OTP (one-time pad) protection registers. These one-time programmable registers can be used to increase system security. Intel factories program a unique, unchangeable 64-bit number into the OTP, and the customer as desired can program other 64-bit register. Once programmed, the customer segment can be locked to prevent further reprogramming. The OTP information can be used for manufacturing tractability and/or a small-encrypted security key for system authentication.