Cryptolight: Secret message transmission using LED

In this technologically accelerating era, wireless message passing is playing an exceptional role. These messages being transmitted over an open environment is vulnerable to various security threats. To hold back these impedances several cryptographic measures have been introduced. Computation complexities, key management etc are some of the common hindrances that the existing cryptographic techniques face. The proposed system, Cryptolight, uses visible light communication channels for transmission. The system is completely immune to radio frequency attacks. The data is encoded as LED blinks in the sender side and reacquired at the receiver side by the process of image processing. Key board, display device, PIC board and an LED strip constitutes the sender side. The receiver side incorporates a camera, Raspberry-pi and a display device. Filters are employed in order to diminish the effect of noise. The display device and the key board is connected to the LED strip with the PIC board as the interface. The input text is converted into LED blinks, and is captured using camera at the receiver side. These images are later processed in the Raspberry-pi to retain the text.