Data Encryption Research Paper

Information transmission and exchange over shared channels such as Internet, Intranet…etc, becoming a more necessity for all fields in our daily life. It is therefore possible for any user to intercept the sensitive data that is transmitted over the shared channel. So information security and data encryption are becoming more and more important. Information encryption techniques have been an important and active research area from ancient time to nowadays, which involves a number of applications such as military communication, intellectual properties protection, information security, to name a few. One of the major purposes of data encryption is that one is able to encode data to be sent in such a way, that it is difficult for an unauthorized

Among them are double random phase encoding (DRPE) [1], digital holography [15], Fractional Fourier transform FrFT [5], [10], optical exclusive- OR [45], virtual (digital) optics [43], watermarking, and polarization [45]. These techniques use a complete optical set up which include; source light, lenses, mirrors, splitters, spatial filters, gratings…etc.

Conventional optical encryption techniques are based on the classical 4-f system architecture ,see figure 1.1, [1][44][22], A two-lens processor, that uses two fixed random phase-masks one in the input and the other in the Fourier plane, respectively. In this technique the original image will converted into a stationary white noise [1] and the encrypted data is complex and have to be stored holographically. To record high quality approximations of both the amplitude and phase of complex valued wavefronts output by the optical encryption systems, digital holographic techniques have been used. Figure 1-1 The classical 4-f

The dynamic mode profile can be accurately estimated as the wave propagates through the wave guide. In this method, a mode is essentially decomposed into a superposition of plane waves, each traveling in a different direction. These individual plane waves will propagate through a finite predetermined distance through the wave guide until the point where the field needs to be determined has arrived. At this point, all of these individual plane waves are numerically added to get back the spatial mode