A chaos-based joint compression and encryption scheme for streaming data

Three Techniques for Enhancing Chaos-Based Joint Compression and Encryption Schemes

“…The approach presented in [ 13 ] dynamically updates the LUTs during the searching process in [ 12 ]. This dynamic updating mechanism removes the overhead of storing numerous LUTs needed in [ 12 ] and takes advantages of local features of the plaintext to provide better compression ratio, for dealing with streaming data.…”

“…As a modification of [ 12 ], the streaming scheme proposed in [ 13 ] also uses NCBPs. Real-number LUTs, which can be easily and efficiently tuned, are included.…”

“…The real-number LUT corresponding to the subset is updated per plaintext symbol, according to the NCBP of the last W bigrams of the subset. Finally, the Huffman coding step used in [ 12 ] is replaced by dynamic Huffman coding presented in [ 13 ]. Notably, the dynamic nature of this scheme makes it possible to process the input stream in only one pass.…”

“…A chaos-based cipher using a key-dependent chaotic trajectory was designed by Baptista [ 8 ]; however, it suffers from the shortcoming of huge ciphertext expansion. Attempts were made in [ 9 , 10 , 11 , 12 , 13 ] to incorporate certain compression capabilities into the Baptista-type chaos-based cipher systems.…”

“…In the proposed model, we exponentially weight the plaintext symbols in the stream and take the weighted average occurrence probability as an estimate. In contrast to the method presented in [ 13 ], our model retains information with respect to older symbols in the stream. As a result, it provides a more accurate estimate of the occurrence probability distribution.…”