A New Encoding Decoding Scheme for Text Compression with Embedded Security

In today's communication world, finding out and improving the means of better channel utilization, as well as providing the security of data transmitted are the key issues. For some data types, e.g. text, full (lossless) data recovery might also be required. Therefore, a lossless compression algorithm that is reasonably fast and secure enough would meet the needs of many in the networking environments. While standard compression tools (e.g. gzip of Unix and pkzip of Windows platforms) achieve compression rates at around 3 bpc (bits per character) for text type of data, they are poor at security. This study presents the design and implementation of a new encoding/decoding scheme to offer compression and security at the same time. For that, the scheme combines compression with encryption. To address the security issue, encoding is made through an Encoding matrix generated by a Pseudo Random Number Generator. This encoding already provides an initial compression. It then uses Arithmetic Coding to further compress the text. For further security, an iterative encoding scheme is proposed and implemented. The results obtained are encouraging in terms of both compression and security.