Digital Right Management Model based on Cryptography for Text Contents

Generally, DRM (Digital Rights Management) system is achieved with individual function modules of cryptography, watermarking and so on. In this typical system flow, all digital contents are temporarily disclosed with perfect condition via decryption process. This paper describes the fundamental idea of a novel DRM method which is composed of an incomplete cryptography and user identification mechanism to control the quality of digital contents. This research paper proposes an improved scheme to encrypt the plain text message for its security. All the conventional encryption techniques are very weak and brute force attack and traditional cryptanalysis can be used to easily determine the plain text from encrypted text. In this work of encryption technique, a new concept of conventional ceaser cipher algorithm with hill cipher algorithm is used to make encryption technique more secure and stronger than the earlier concept. The plain text is encrypted in such a way that it becomes difficult to decrypt it. The proposed system is divided into two phases. In first phase, the plain text message is converted to first encrypted text using a new substitution approach which uses polyalphabetic cipher technique. The encryption is done using variable length key which depends on the string length. In the second phase, the hill cipher technique is applied on the first encrypted text to produce new encrypted text or cipher text. At the receiver end, if the receiver has appropriate decryption key, he can generate the text message similar to the original message. DRM is a form of cryptography, the process of protecting information from unauthorized use by transforming it so that only the authorized receiver can read it. The sender – in this context, the information vendor or provider – encrypts the digital object via a “key” of some kind. The recipient – the information user – may decrypt it for use with a copy of the same key, usually automatically. The information is protected from “attackers” – unauthorized users, or uses – who lack the key. Encryption Standard (AES). Features of data are depends on its types. Therefore same encryption technique cannot be used used for all types of data. Images have large data size and also has real time constrain problem hence similar method cannot be used to protect images as well as text from unauthorized access. However with few variations in method AES can be used to protect image as well as text. In this project I have implemented encryption and decryption for text and image using AES. Index Terms – Key Based Interval Splitting (KSAC), Advanced Encryption Standard (AES).