Skip to Main Content
One of the most useful features in any personal digital assistant (PDA) is that it can accumulate information needed including easy-to-forget details. Some of the information stored is likely to be very sensitive including credit card numbers, personal identification, and passwords. To protect this sensitive data, most PDAs offer password protection as a basic authentication. However, to rely on this type of protection alone is not enough. As the writing of secret message cryptography, also known as science and mathematical lock and key (Schafer, 2003), evolved people rely on the encryption process to increase their level of data protection.