International Journal of Computer Applications (0975 – 8887) Volume 79 – No.1, October 2013 21 An Evaluation of Data Security for Telemedicine Application Development Hetal N. Rao PG Research Scholar Department of Electronics and Communication RK University, Rajkot, India Manoj Pandya Senior Project Scientist BISAG Gandhinagar, India K M V V Prasad Assistant Professor Department of Electronics and Communication RK University, Rajkot, India ABSTRACT Digital Communication has made the data transfer and data communication very fast, easy and efficient. In the field of the data security several techniques are used right from the years ago. This includes Cryptography, Steganography and Watermarking techniques. This paper includes the review and comparative analysis of all these three techniques for the field of Image Processing focusing to the Medical Images. As for Healthcare field, security of data is more sensitive and important, we are analyzing for the most suitable technique for this purpose. This review is initial part of the research for developing the application of data security using efficient algorithm that follows the specific and robust transformation technique useful in Telemedicine field. General Terms Data Security, Data Hiding Keywords Cryptography, Steganography, Watermarking, Copyright Protections, Intellectual Rights 1. INTRODUCTION According to communication progress, Internet has become the most common source of data sharing and transfer. In this activity of data communication, security, copyright, hacking etc. are the factors upon which we need to focus as well. Three key technologies are there for it: Cryptography, Steganography and Watermarking (a subcategory of steganography-as per the various researchers). In the modern era of technology, multimedia has become the most popular medium for data transfer. Among various multimedia objects like video, audio, pictures/ images, we are here merely focusing on ‘Image’. Therefore this review is more concerning to compare and analyze all above technologies particularly for image data. If take a glance towards the above mentioned three techniques - Cryptography is the process of scrambling the information or data using different keys as Public key and Private Key. Cryptography performance is based on two fundamental share which are Encryption and Decryption that are used at sender and receiver end respectively. Disadvantages of Cryptography made the basis for development of its next generation, Steganography. In last few years, the research has grown in digital image steganography techniques. The major goal of steganography is to achieve security by inserting the data to be hidden within an image by altering the non-data containing pixels. The image after including the secrete message/data to be hidden is called stago image. The main difference between cryptography and steganography is that in case of cryptography, only the data content is kept hidden and its existence is not made hidden. Whereas in case of steganography, both the data existence and data itself. Steganography (Cover writing) Detection (Data Hiding) Protection against Detection Removal (Document Marking) Watermarking Finger Printing Fig 1: Divisions of Steganography [3] As per mentioned in the diagram in fig. 1, watermarking is considered as a specific type of the steganography itself. Watermarks are having two types as visible watermark and invisible watermarks. The visible watermarks are as per the name indicates, are having visibility by naked eyes and those, named as invisible, cannot be seen having embedded within the cover image after watermarking. Again there are other classifications of the watermark types as fragile and semi fragile, blind and non-blind, perceptible and imperceptible etc. 2. HISTORY Initially, for the purpose of data security, Cryptography had been used from year 1900 in Egypt. At that time, nonstandard methods were used. During 50 - 60 B.C. Julius Caesar used a simple substitution with the normal alphabet in government communications. From 500 – 600 B.C. Hebrew scribes used ATBASH, a reversed alphabet simple solution cipher [5]. Cryptography had been continued with many variations. Steganography has been developed through a longer history of Cryptography. The origin of Steganography is the word ‘Steganos’ means covered/secrete. It was developed by Sir Francis Bacon. Initially, it had been originated in Greece. The Greek ruler Histaeus engaged an early version of steganography which involved: shaving the head of a slave, tattooing the message on the slaves scalp, waiting for the growth of hair to disclose the secret message, and sending the slave on his way to deliver the message. The recipient would have the slave’s head to uncover the message. The recipient would reply in the same form of staganography [5]. The other early form developed for the Cryptography. It involved Demerstus who had written a message for Spartans to warn from the eminent invasions by Xerxes. It was written on wood covered by wax layer which made to seem the tablet being empty but in fact it was containing a secrete message. Watermarking is more popular technique in today’s modern communication for data security especially for the purpose of