CHAOS BASED ENCRYPTION NEIL PARMAR DEPARTMENT OF COMPUTER SCIENCE

ENCRYPTION Medical systems In this paper, Electroencephalograms (EEGs) – brain waves and can be used to detect epilepsy and other diseases – Mood Swings – Cognitive functions of the patients – 16-Channel EEG Visual User Environment Scheme Goal: To create a robust and real-time chaos-based image encryption functionality.

Figure Channel EEG Vue Signals

Chaos Based Encryption System for Encrypting Electroencephalogram Signals 1.Purpose a)Encrypt the medical EEG 16-channel EEG Vue Signals. b)Generate robust and real-time encryption c)Electroencephalograms Visual User Environment Signals are encrypted 2.Unique Approach a)Microsoft Visual development kit and C# Programming language b)Three Level Approach 3.Overview a)C# based Level I, II, III chaos-based encryption algorithm. b)Level I uses bifurcation parameters, chaotic map and initial value to achieve high- speed, real-time encryption. c)Threshold parameters were added in Level II to enhance level of robustness. d)In Level III, moreover to all the above parameters, a bit stream address index assignment strategy is incorporated in order to achieve the most robust level encryption.

Algorithm LEVEL I STEP 1: Enter the starting point x, and bifurcation parameter r STEP 2: Generate a chaotic sequence of (Length of the clinical EEG Vue signal bit stream (EEGS)) length L F c n+1 = CMT (c n ); c 0 = x; n = {1,2,…..L F } (1) i.e., c n+1 = rc n (1-c n ) STEP 3: The A Chaos-based encryption bit streams (CBEBS) are generated as follows CBEBS = {y n } n = {1,2,…..L F } y n = {1 c n >= 0.5} y n = {0 c n < 0.5} STEP 4: Deliver Electroencephalograms Visual User Environment Signal Bit Stream of Length L F EEGS = {eeg 1, eeg 2, eeg 3,……eeg LF }

STEP 5: Generate encrypted Generated encrypted clinical Electroencephalogram Visual User Environment Signal Bit Streams (GEEG) GEEG = EEGS CBEBS +

Limitation of Level I The starting point and the chaotic map can be easily tracked.

LEVEL II STEP 1: Enter the starting point x, bifurcation parameter r, CMT, bit stream length L F, number of discarded initial chaotic index points nF(10<=nF<= ), and level of security dF(0.01<=dF<=0.99). STEP 2: (a) c 0 = x (b) Generate nF chaotic points c n+1 = CMT(c n ) then discard them. STEP 3: (a) c nF + 1 = CMT F (c nF ) (b) If c n >dF then discard this point and go to step 3 (a); otherwise perform step 3(c). (c) Generate a chaotic sequence of length L F. c n ; n = {1,2,3,…..L F }

STEP 4: The A Chaos based encryption bit streams (CBEBS) is generated as follows: CBEBS = {y n } n = {1,2,…..L F } y n = {1 c n >= 0.5} y n = {0 c n < 0.5} STEP 5: Deliver Electroencephalograms Visual User Environment Signal Bit Stream of Length L F EEGS = {eeg 1, eeg 2, eeg 3,……eeg LF } STEP 5: Generate encrypted Generated encrypted clinical Electroencephalogram Visual User Environment Signal Bit Streams (GEEG) GEEG = EEGS CBEBS +

Scope for Level III In Order to enhance the security, the paper introduces the Level III security.

LEVEL III C#- based Level III encryption algorithm, which is described as follows: A chaotic logistic map was employed in the chaotic maps CMT F and CMT. CMT is the chaotic map of G CCS, the chaotic candidate point generator process. CMT F is the chaotic map of F CIA, the chaotic address index assignment process STEP 1: Enter the starting points x, and x2, length L F, number of discarded initial chaotic index points nF, and the level of security dF. STEP 2: Generate nF chaotic points c n+1 = CMT(c n ) and then discard them. STEP 3: (a) c n+1 = CMT(C n ) (b) The initial value of index j is 1, and j=j+1 m j = 1 c n+1

Step 4: [compare m j and the previous m k, 1<=k<=j-1 ] If m j {m k, 1<=k<=j-1}, then discard this point and go to step 3; otherwise proceed to the next step. Step 5: If j>= L F, terminate the procedure, output m j, 1<=j<=L F, and perform the next step; Otherwise, go to step 3. Step 6: [ F CIA : generate the chaotic index address assignment ] (a) 1<=j<=L F, m j N F CIA : M = {m 1, m 2, m 3,…. m LF } (b) m C * = maximum index address = max 1<=j<=LF m j Step 7: Input x2, the starting point for CMT G. y n+1 = CMT G (y n ), y 0 = x2; Step 8: If y n >dF then discard this point and go to step 7; otherwise, perform the next step.

STEP 9: Generate a chaotic sequence with a finite length m c * by performing the following iterative algorithm: Y = {y 0, y 1, y 2,…. Y mc* } STEP 10: Generate a chaotic sequence of length L F. Z n = {z 0, z 1, z 2,…. z LF } = {y m0, y m1, y m2,…. Y mLF }; STEP 11: The A Chaos based encryption bit streams (CBEBS) of W is generated as follows: CBEBSW = {w n } n = {1,2,…..L F } w n = {1 z n >= 0.5} w n = {0 z n < 0.5}

STEP 12: Deliver Electroencephalograms Visual User Environment Signal Bit Stream of Length L F EEGS = {eeg 1, eeg 2, eeg 3,……eeg LF } STEP 13: Generate encrypted Generated encrypted clinical Electroencephalogram Visual User Environment Signal Bit Streams (GEEG) GEEG = EEGS CBEBSW +

Limitations of the Paper Microsoft-based operating system. Speed, is it necessary for encryption?

Thank You Any Questions?

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