Robust encryption of data by using nonlinear
systems
A new method is proposed for data encryption
by using various nonlinear systems (Robot equation, Duffing oscillator, etc.) which provides
an effective protection of data from unauthorized modification and use during its storage and
transmission.
In order to generate chaotic sequence, a simple nonlinear one-dimensional robot model has been used.
The system is described with the nonlinear
differential equation of the second order in time,

which corresponds to
the hard spring with coefficients
and
,
with two types of friction. On the right side of equation, we have the
periodic time-dependent force with amplitude
,
and feedback force with the corresponding
parameters,
,
,
,
,
,
.
PATENTS APPROVED BY THE
STATE INTELLECTUAL PROPERTY OFFICE IN CROATIA:
-
"Cryptographic method of nonrepeated selective assignment
of signs using chaotic
solutions of robotic differential equation ", in Croatian,
State
intellectual property office, Croatia, Patent Nr. P980607 (2003).
-
"Cryptographic method by repeated application of binary ASCII
code depending on parity of digits in chaotic
solutions of nonlinear robotic equation", in Croatian,
State intellectual property office, Croatia, Patent Nr. P990240A2
(2006).
-
"Cryptographic protection of series of signs using selective
transformation of binary ASCII code using chaotic solutions of
nonlinear Duffing equation", in Croatian
, State intellectual property office, Croatia, Patent Nr. P990248A2
(2006).
Literature:
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29-42 (1989).
- W.H. Press, B. P. Flannery, S. A. Teukolsky, and W. T. Vetterling, Numerical Recipes, Chapter
7.5 Data Encryption Standards, Cambridge University Press, Cambridge (1988).
- Data Encryption Standard, Federal Information Processing Standards Publication, No.
46 (U.S. Department of Commerce, National Bureau of Standards, Washington, D.C., 1977).
- M. Bianco, An encryption system based on chaos theory, European Patent Office,
Publication No. 0 467 239 A2 (1991).
- T.L. Carroll, Synchronizing chaotic systems using filtered sygnals, Physical
review E50, 2580-2587 (1994).
- U. Parlitz, S. Ergezinger, Robust communication based on chaotic spreading sequences,
Physics Letters A188, 146-150 (1994).
- S.Hayes, C. Grebogi, E. Ott, Communicating with Chaos, Physical review Letters
70, 3031-3034).
- A. Oksasoglu, T. Akgul, Chaoting masking scheme with linear inverse system, Physical
Review Letters 75, 4595-4597 (1995).
Nils Paar, 1999.
