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From the ancient days to the information age of today, the volume of information has increased million-fold and acquired economic significance in the context of billions of dollars worth e-commerce. The present socio economic scenario demands speedy transfer of information with enhanced security. In this context, cryptography acquires far greater significance. Cryptography is a method of storing and transmitting data in a secret form which allows correspondence only between the intended persons. The security and speed are obviously two most important parameters in public key cryptosystem. Whenever the security increases, it results in the decrement of speed of crypt process. Hence there is a need for a cryptography algorithm which can optimise both these parameters. In this book,Security is achieved through the proposed algorithms MRGA and ABCRNG. The speed of the algorithm is also enhanced on implementing the algorithms MsgEncA and ModBlockExpoA. The PKCrypt tool has been introduced to support both text and image files. This book will be of useful for researchers working in communication network in the aspect of Security.

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Dr.J.Sai Geetha is serving as an Assistant Professor of Computer Science at Nehru Memorial College, Tiruchirappalli,India. Dr.D.I.George Amalarethinam is Bursar & Director-MCA of Jamal Mohamed College, Tiruchirappalli, India. The authors have several National, International publications and books to their credits.

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