Implementation of some privacy preserving techniques

Abstract

The demand of privacy acts as a key factor in increasing the importance of communication newlinesecurity. The effort started long back in 499 BC when Greek tyrant Histiaeus shaved the newlinehead of his slave and wrote some secret message on his scalp. After the hair grew back, the newlineslave was dispatched with the hidden message. In another technique, Pliny the Elder newlineexplained the use of the milk of Thithymallus plant which dries to transparency when newlineapplied to paper but darkens to brown when subsequently heated. Effort was also made by newlineGiovanni Battista Porta to conceal a message within a hardboiled egg by writing on the newlineshell with a special ink. In World War II secret messages were disguised in long sentences newlineof regular letters. With the tremendous advancement in digital signal processing, use of newlineinternet and computing power, the hiding technique became digital. The process starts by newlineidentifying a cover image and then its redundant bits are modified without destroying the newlineintegrity. newline