KR20190104728A - Apparatus and Method for Encrypting Based on Combined Chaos in Body Area Network - Google Patents

Abstract

The present invention relates to an apparatus and method for encryption based on chaos in a body area network. According to the present invention, in the method for encryption based on chaos in a body area network, sub-chaos matrices based on one-dimensional chaotic sequences generated by logistic chaotic mapping and Kent chaotic mapping are generated in an original image. The method for encryption combines two sub-chaotic matrices to obtain a chaotic encrypted matrix, and performs an XOR operation on an initial data matrix and the chaotic encrypted matrix to obtain an encrypted image.

Description

Apparatus and Method for Encrypting Based on Combined Chaos in Body Area Network}

The present invention relates to an encryption method, and in particular, a sub chaotic matrix according to a one-dimensional chaotic sequence generated by Logistic Chaotic Mapping and Kent Chaotic Mapping in the original image is generated, The present invention relates to an apparatus and method for chaos based encryption in a body area network which combines two sub-chaotic matrices to obtain a matrix and performs an XOR operation on an initial data matrix and a chaotic encrypted matrix.

In the body area network (BAN), data encryption at the sensor node is very important because the physiological data of the individual is very sensitive.

However, past encryption methods are vulnerable to attack because of the small key space.

Along with the need for networks and the proliferation of chronic diseases such as high blood pressure and diabetes, applications related to wireless networks around the human body have attracted a great deal of attention, leading to the emergence of a body area network (BAN), a wearable system that connects sensors and nodes.

As shown in Figure 1 may be disposed in, around or around the human body.

BANs can obtain human vital signs that support remote biopsy, emergency care and health information services.

For users, biosignal information is very private and can only be accessed by authorized authorities. Security is essential in BANs. BAN supports identity verification, privacy and information integrity. Existing encryption techniques apply to many areas.

BAN has been researched and applied to many encryption methods such as key distribution method and encryption and decryption algorithm.

However, because of the limited source of BAN nodes, key pre-deployment schemes, key distribution centers, RSA public key infrastructures, and elliptical function public key infrastructures are not suitable for BAN applications. As a first method, encryption and decryption algorithms require a large number of operations, resulting in a sharp increase in power consumption, which is not suitable for BAN systems given the extreme low power BAN node requirements.

The second method can arbitrarily generate a symmetric key between communication aspects of the physical layer using the characteristics of the BAN channel as a key.

The second method generates a key in the receiver according to the calculated radio channel signal strength. Because the distance between the eavesdropper and the receiver is not constant, the signal strength values are different so that the eavesdropper cannot decode the data.

However, this second method has a problem that can fail when the transmitter has the same distance as the eavesdropper and the receiver.

The third method generates a key according to the biosignal information. Unlike typical sensor network nodes, the parameters of the BAN node are human physiological signals and represent different functions for different individuals. Even for the same individual, the value changes slowly over time.

Although a key generation approach using physiological parameters is suitable for BAN systems, there are problems in that the unique values of some parameters are similar without apparent change over time and the encryption strength is weak.

The conventional encryption method described above has disadvantages of low resistance and sensitivity because it has a disadvantage of weak encryption strength.

Korean Patent No. 10-1502930 ("Name of the invention: Asymmetric Chaos Encryption")

In order to solve this problem, the present invention generates a sub-chaose matrix according to the one-dimensional chaos sequence generated by Logistic Chaotic Mapping and Kent Chaotic Mapping on the original image, respectively, and the chaotic encryption To provide a chaos-based encryption apparatus and method in a body area network which combines two sub-chaotic matrices to obtain an encrypted matrix and performs an XOR operation on an initial data matrix and a chaotic encrypted matrix to obtain an encrypted image. There is this.

An apparatus for chaos based encryption in a body area network according to an aspect of the present invention for achieving the above object,

An image input unit reading an original image I (i, j) to form an original image data matrix T;

A logistic chaotic mapping unit constituting a sub-chaotic matrix Sl, which is a sub-matrix according to a one-dimensional chaotic sequence generated by logistic chaotic mapping;

A kent chaotic mapping unit constituting a sub-chaotic matrix Sk, which is a sub-matrix according to a one-dimensional chaotic sequence generated by kent chaotic mapping;

An encryption matrix combiner that combines the sub-chaotic matrix Sl and the sub-chaotic matrix Sk to form a chaotic encrypted 2-dimensional chaotic matrix Ec; And

And an encrypted image generator for generating an encrypted image matrix E by performing an XOR operation on the original image data matrix T and the two-dimensional chaotic matrix Ec.

The chaos-based encryption method in the body area network according to an aspect of the present invention,

Reading the original image I (i, j) to form an original image data matrix T;

Constructing a Sub-Chaotic Matrix Sl, which is a sub-matrix according to a one-dimensional chaotic sequence generated by Logistic Chaotic Mapping;

Constructing a Sub-Chaotic Matrix Sk, which is a sub-matrix according to a one-dimensional chaotic sequence generated by Kent Chaotic Mapping;

Combining the sub-chaotic matrix S1 and the sub-chaotic matrix Sk to form a chaotic encrypted two-dimensional chaotic matrix Ec; And

And performing an XOR operation on the original image data matrix T and the two-dimensional chaotic matrix Ec to generate an encrypted image matrix E.

By the above-described configuration, the present invention has the effect that the combination of Logistic chaos mapping and Kent chaos mapping improves the security of the encryption of the chaos system and provides a system with high resistance and sensitivity.

The present invention has the effect of having a large key space, high key sensitivity, excellent attack resistance, and suitable for privacy protection of a BAN system.

1 is a diagram conceptually showing a configuration of a conventional body part network.
2 is a diagram illustrating a configuration of a chaos-based encryption device in a body area network according to an embodiment of the present invention.
3 is a diagram illustrating an example of logistic mapping according to an embodiment of the present invention.
4 illustrates a time series of Kent mapping according to an embodiment of the present invention.
5 is a diagram illustrating a chaos-based encryption method in a body area network according to an embodiment of the present invention.
6 is a view showing the experimental results for the original gray image according to an embodiment of the present invention.
7 is a view showing the experimental results for the original color image according to an embodiment of the present invention.
8 is a diagram illustrating a correlation between different directions of an original gray image and an encrypted gray image according to an exemplary embodiment of the present invention.
9 illustrates key sensitivity test results of a gray image according to an exemplary embodiment of the present invention.
10 illustrates key sensitivity test results of a color image according to an exemplary embodiment of the present invention.

Throughout the specification, when a part is said to "include" a certain component, it means that it can further include other components, without excluding other components unless specifically stated otherwise.

The present invention proposes a new encryption algorithm based on the combined chaos. First, two partial matrices are created by using Logistic Chaos Mapping and Kent Chaos Mapping, and then a combined matrix is generated by performing XOR operation on the original data and encrypting them.

Experimental results show that the proposed algorithm has a large key space, high key sensitivity, excellent attack resistance, and is suitable for privacy protection of BAN system.

The combined use of chaotic systems can improve the security of encryption. In the present invention, we propose an algorithm using Logistic Chaos Mapping and Kent's Chaos Mapping, and a new method for generating a two-dimensional chaotic matrix for data encryption.

This method can achieve a large key space, high key sensitivity and excellent attack resistance.

1 is a diagram illustrating a configuration of a chaos-based encryption device in a body area network according to an embodiment of the present invention.

In the body area network according to an embodiment of the present invention, the chaos-based encryption apparatus 100 includes an image input unit 110, a logistic chaos mapping unit 120, a kent chaos mapping unit 130, an encryption matrix combiner 140, and the like. Encrypted image generating unit 150 is included.

There is a natural connection and structural similarity between chaos and cryptography. The sensitivity of the initial value in chaos is directly related to the trajectory, leading to the mixing characteristics of the chaotic trajectory. This sensitivity corresponds to the spreading characteristic of the cryptographic system, and the random similarity characteristic of the chaotic signal corresponds to the chaotic characteristic of the cryptographic system.

Chaos mapping is essential to the generation of digital discrete chaos sequences in the design process of cryptographic systems. Chaos phenomena can be represented by certain nonlinear systems, but whether a nonlinear system causes a chaotic phenomenon depends on the value of the control parameter.

In constructing a mathematical model of the chaotic system, the chaotic system is adapted to achieve a chaotic state according to different chaotic phenomena and parameters.

Chaos mapping is a nonlinear chaos equation and one of the most common chaos models widely used in confusing image encryption algorithms.

Kent mapping is a widely used chaotic system with good performance. Therefore, the encryption method of the present invention generates a chaotic sequence by applying logistic mapping and kent mapping. Periodic Doubling Bifurcation is a common way of making chaos. Logistic mapping represents a nonlinear system with increasing control parameters, creating a doubling phenomena and achieving chaotic states, as shown in Equation 1 below.

Where μ is a parameter for nonlinear intensity control and Xn represents the value of the state variable after the nth iteration. When μ ∈ [3.5699456, 4], X n ∈ [0, 1], and n ∈ N, the encryption apparatus 100 is in a chaotic state. 3 shows logistic mapping. Kent mapping has high sensitivity to initial conditions. The trajectory can be predicted in the short term but not in the long term. Kent mapping is shown in Equation 2 below.

Where a is a control parameter. When 0.4 <a <0.5 and Yn ∈ [0, 1], the cryptographic apparatus 100 is in a relatively ideal chaotic state. 4 illustrates the time series of Kent mapping.

In a BAN system, large amounts of data are stored as images. Thus, the present invention uses an image format to describe and test the encryption algorithm.

In the original image I of size M × N, I (i, j) represents pixel data located at (i, j) and forms an original image data matrix T. A chaos based encryption method in the body area network proposed in the present invention is illustrated in FIG. 5.

The chaos-based encryption method in the body area network of the present invention undergoes the following steps.

The image input unit 110 reads the original image I (i, j) to form the original image data matrix T (S100).

The logistic chaotic mapping unit 120 sets initial parameter values of X ₀ and μ in Logistic Chaotic Mapping (Equation 1) (S102), and the sub chaotic matrix (Sub) according to the generated one-dimensional chaotic sequence. -Chaotic Matrix) Sl (S104).

을 가진 1차원 카오스 시퀀스

를 생성한다. 그런 다음 1차원 카오틱 시퀀스 X의 행과 열의 수가 재조정된다.The logistic chaos mapping unit 120 sets an initial value of the iteration X ₀ and a parameter μ, and the encryption apparatus 100 is in a chaotic state.

-Dimensional chaotic sequence with

Create The number of rows and columns of the one-dimensional chaotic sequence X is then readjusted.

의 값은 순서대로 얻어지고 2차원 행렬 Sl의 열에 순차적으로 채워진다. 마지막으로, 크기 M×N₁의 2 차원 서브 카오스 행렬 Sㅣ이 생성된다.

The values of are obtained in order and are sequentially filled in the columns of the two-dimensional matrix Sl. Finally, a two-dimensional sub-chaotic matrix S | of size M × N ₁ is generated.

The kent chaos mapping unit 130 sets initial parameter values of Y ₀ and a in Kent chaos mapping (Equation 2) (S106), and constructs a sub-chaotic matrix Sk according to the generated one-dimensional chaotic sequence. (S108).

(여기서, N₂ = N - N₁)의 서브 카오스 행렬 Sk의 구성 과정은 서브 카오스 행렬 Sl의 구성 과정과 동일하다.size

(Here, N ₂ = N-N ₁ ) The configuration process of the sub-chaotic matrix Sk is the same as the configuration process of the sub-chaos matrix Sl.

and N₂=N-ceil(N/2)을 가진 1차원 카오스 시퀀스 Y={Y₁, Y₂..., Yn₂}를 생성한다. 그런 다음 1차원 카오틱 시퀀스 Y의 행과 열의 수가 재조정된다.The kent chaos mapping unit 130 sets an initial parameter value of a of iteration Y ₀ , and the encryption apparatus 100 is in a chaotic state.

and generate a one-dimensional chaotic sequence Y = {Y ₁ , Y ₂ ..., Yn ₂ } with N ₂ = N-ceil (N / 2). The number of rows and columns of the one-dimensional chaotic sequence Y is then readjusted.

The values of Y = {Y ₁ , Y ₂ ..., Yn ₂ } are obtained in order and are sequentially filled in the columns of the two-dimensional matrix Sk. Finally, a two-dimensional sub-chaotic matrix Sk of size M × N ₂ is generated.

The encryption matrix combiner 140 combines the sub-chaose matrices Sl and Sk to obtain a chaotic encrypted matrix Ec (S110).

Logistic chaos mapping and Kent chaos mapping have been carefully studied, but when used alone, they have small key spaces, less security, and limited system accuracy. The encryption matrix combiner 140 combines the logistic chaotic mapping and the kent chaotic mapping to generate a two-dimensional chaotic matrix. The join expression is shown in Equation 3 below.

The encrypted image generator 150 generates an encrypted image matrix E by performing an XOR operation on the original image data matrix T and the final encrypted matrix Ec to obtain the final encrypted image E (S112 and S114).

Decryption algorithms are the reverse of encryption algorithms.

(1) visual results analysis

Compare the original and encrypted images according to the reference criteria. In the experiment, the initial parameter values of logistic chaos mapping are X ₀ = 0.36, u = 3.970. The initial parameter value of Y ₀ in the kent chaos mapping is the result after performing the k iteration loop shown in [Equation 1]. Where k = 500 for logistic chaotic mapping. The initial parameter value of kent chaos mapping is 0.414.

The encrypted gray image and pixel histogram are shown in FIG. 6. The encrypted color image and pixel histogram are shown in FIG. The histogram shows the distribution characteristic of the gray level.

As shown in Figs. 6 and 7, the distribution of the histograms for the original gray image and the color image is nonuniform, and the distribution of the histograms for the encrypted gray image and the color image is uniform, indicating good scrambling characteristics of the encrypted image. In addition, it can be seen that the information of the plain text image is effectively concealed.

Figure 6 shows the experimental results for the original gray image. (A) of FIG. 6 is an original gray image, FIG. 6 (b) is an encrypted gray image, FIG. 6 (c) is a histogram of an original gray image, and FIG. 6 (d) is an encrypted gray image. Histogram of.

Figure 7 shows the experimental results for the original color image. FIG. 7A is an original color image, FIG. 7B is an encrypted color image, FIG. 7C is a histogram of R components of the original color image, and FIG. 7D is an original color image 7 (e) is a histogram of the B component of the original color image, FIG. 7 (f) is a histogram of the R component of the encrypted color image, and (g) of FIG. Is a histogram of the G component of the encrypted color image, and FIG. 7 (h) is a histogram of the B component of the encrypted color image.

(2) Quantitative Results Analysis

Since many adjacent pixels of the original image have the same or similar gray levels, the effect on the encryption method of the present invention is observed through the correlation of adjacent pixels. The correlation of adjacent pixels in the horizontal, vertical and diagonal directions is defined as follows.

Where x and y each represent gray values of two adjacent pixels, M and N are the number of rows and columns for the image, and MN is the total number of pixels. The present invention represents a scatter plot of pixel correlation by randomly selecting between 1000 and 3000 pixel pairs in all directions of the original and encrypted images.

8 shows the correlation of different directions of the original gray image and the encrypted gray image. (A) of FIG. 8 is a correlation scatter plot of the original gray image, and FIG. 8 (b) is a correlation scatter plot of the original gray image, and FIG. Correlation scattering plot of the original gray image in the diagonal direction, Figure 8 (d) is a horizontal correlation scattering plot of the encrypted gray image, Figure 8 (e) is a vertical correlation scattering plot of the encrypted gray image 8 (f) is a correlation scatter plot of a diagonal direction of an encrypted gray image.

As shown in (d), (e), and (f) of FIG. 8, compared to the correlation scattering plot according to the ciphertext image, it is more concentrated than the correlation scattering plot according to the plaintext image so that the encryption method converts the plain text to the ciphertext. To achieve.

The correlation between the original image and the encrypted image in the horizontal, vertical, and diagonal directions is listed in Table 1 and Table 2, respectively.

Table 1 shows the correlation between the original gray image and the encrypted gray image.

Table 2 shows the correlation between the original color image and the encrypted color image.

Since the correlation value of the original image in all directions is 0.9 or more, the gray level of adjacent pixels is similar and the correlation value of the encrypted image is close to 0, so that the gray levels of adjacent pixels are different, thereby improving resistance to attack. In general, the smaller the fixed-point ratio between an encrypted image and the original image, the greater the difference between the two images and the greater the scrambling effect. The number of pixel change rates (NPCR) is represented by the following Equations 8 and 9 below.

Here, C ₁ (i, j) and C ₂ (i, j) represent the gray values of the plain text and the cipher text at the pixels (i, j), respectively, and D (i, j) at the pixels (i, j). Indicates the change between plaintext and ciphertext. In addition, the information entropy of the ciphertext is used to measure the average uncertainty of the ciphertext. When the gray value of the ciphertext is equally likely, the information entropy of the image reaches a maximum value of 8 and an ideal random image feature is achieved.

The information entropy of the image is expressed as in Equation 10 below.

Here, P (m (i)) represents the occurrence probability of the gray value i. When the value of ciphertext entropy is close to outlier 8, the encrypted image has strong average uncertainty and high resistance to statistical and entropy attacks.

In Tables 3 and 4, the encryption method proposed in the present invention is compared with other encryption algorithms based on combined chaos.

Table 3 compares the performance of the algorithm of the original gray image and Table 4 compares the performance of the algorithm of the original color image.

In Table 3, reference [20] does not provide NPCR values. Of all these methods, the encryption method (algorithm) of the present invention obtains the maximum NPCR value. The H value obtained in the algorithm of Reference [15] is slightly larger than the encryption method of the present invention, but the encryption method of the present invention is generally excellent in scrambling effect and sensitivity against plain text, and thus has a strong resistance to differential attack.

(3) spatial analysis of security keys

The composition and size of the key space determine the security of the encryption algorithm. In the encryption method (algorithm) of the present invention, the initial value X ₀ of the logistic mapping, the parameter μ, the initial value Y ₀ of the kent mapping, the parameter a, and the number of iterations are the keys of the encryption algorithm.

보다 작고, 로지스틱 카오스 시스템과 켄트 카오스 시스템을 기반으로 한 암호화 알고리즘보다 훨씬 클 수 있음을 의미한다.If each parameter is represented by twice the number of 15 decimal places, the number of possible values for each parameter is 10 ¹⁵ , which means that

It is smaller and can be much larger than encryption algorithms based on logistic chaos systems and Kent chaos systems.

Therefore, the encryption algorithm proposed in the present invention has sufficient key space and can resist attacks of thorough methods.

The key sensitivity of the ciphertext image is tested. Set the initial value X ₀ of the logistic mapping to 0.3600000000001 and do not change any other parameters.

The results of the gray and color images are shown in FIGS. 9 and 10.

9 shows the results of the key sensitivity test of the gray image. 9A is an encrypted gray image, FIG. 9B is a correctly decrypted gray image, and FIG. 9C is a gray image decrypted with a small change of an initial value X ₀ .

10 shows the results of the key sensitivity test of the color image. 9A is an encrypted color image, FIG. 9B is a correctly decrypted color image, and FIG. 9C is a color image decrypted with a small change in the initial value X ₀ .

Experimental results show that the original image cannot be recovered if the initial value of X ₀ is a minor change of 10 ^-14 . The test results for other initial values are similar. This experiment shows that the proposed encryption algorithm has high key sensitivity, good attack resistance, and strong algorithm security that can be applied to BAN.

This encryption algorithm can also be used in other systems, such as medical imaging systems. In-transit signal encryption is critical for providing security and privacy in magnetic resonance imaging systems.

Security is important in BAN systems considering privacy protection. In the encryption method of the present invention, an encryption algorithm based on chaos is proposed to support privacy protection of a BAN system.

The proposed algorithm reconciles the contradiction between the finite precision operation and the security of the encryption algorithm.

In the proposed algorithm, we generate a lower chaotic matrix using two different chaotic mappings (Logistic and Kent mapping).

First, sub-chaose matrices are generated based on the generated one-dimensional chaotic sequences of the logistic and ent mappings. These two lower chaotic matrices are combined to obtain a chaotic cryptographic matrix.

Finally, an XOR operation is performed on the original image data matrix and the chaotic encrypted matrix to obtain an encrypted image.

The encryption of the Lenna image is tested in terms of visual observation, quantitative analysis and key space analysis. Experiments show that the proposed algorithm of the present invention has important advantages, particularly in correlation analysis and parameter analysis. Good scrambling characteristics, large key space, high key sensitivity and excellent attack resistance can effectively hide image information and are suitable for the privacy related applications of BAN system.

In the present invention, the two-dimensional chaotic matrix is generated by combining Logistic and Kent chaotic mapping, which is very simple and effective.

In addition, the encryption algorithm of the present invention can be extended to other applications such as medical image encryption.

The embodiments of the present invention are not only implemented through the apparatus and / or method, but may be implemented through a program for realizing a function corresponding to the configuration of the embodiment of the present invention, a recording medium on which the program is recorded, and the like. Such implementations can be easily implemented by those skilled in the art to which the present invention pertains based on the description of the above-described embodiments.

Although the embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

100: encryption device
110: image input unit
120: logistic chaos mapping unit
130: Kent Chaos Mapping Division
140: encryption matrix combiner
150: encrypted image generating unit

Claims (9)

An image input unit reading an original image I (i, j) to form an original image data matrix T;
A logistic chaotic mapping unit constituting a sub-chaotic matrix Sl, which is a sub-matrix according to a one-dimensional chaotic sequence generated by logistic chaotic mapping;
A kent chaotic mapping unit constituting a sub-chaotic matrix Sk, which is a sub-matrix according to a one-dimensional chaotic sequence generated by kent chaotic mapping;
An encryption matrix combiner that combines the sub-chaotic matrix Sl and the sub-chaotic matrix Sk to form a chaotic encrypted 2-dimensional chaotic matrix Ec; And
And an encrypted image generation unit configured to generate an encrypted image matrix E by performing an XOR operation on the original image data matrix T and the two-dimensional chaotic matrix Ec. The method of claim 1,
And the logistic chaos mapping unit sets an initial parameter value of X ₀ and μ according to Equation 1 below in the logistic chaos mapping.
[Equation 1]

Where μ is a parameter for nonlinear intensity control and Xn represents the value of the state variable after the nth iteration. when [mu] [3.5699456, 4], Xn [[0, 1] and n [n] N are chaotic. The method of claim 1,
And the kent chaos mapping unit sets an initial parameter value of Y ₀ and a in Equation 2 below in the kent chaos mapping.
[Equation 2]

Where a is a control parameter. When 0.4 <a <0.5 and Yn ∈ [0, 1], it is an ideal chaotic state. The method of claim 2,
The logistic chaotic mapping unit sets an initial value of the iteration X ₀ and a parameter μ, and becomes a chaotic state.

-Dimensional chaotic sequence with

Create it. An apparatus based on chaos in a body area network, wherein the number of rows and columns of the one-dimensional chaotic sequence X is readjusted. The method of claim 1,
The kent chaos mapping unit sets an initial parameter value of a of iteration Y ₀ , and the encryption apparatus is in a chaotic state.

and generates a one-dimensional chaotic sequence Y = {Y ₁ , Y ₂ ..., Yn ₂ } with N ₂ = N-ceil (N / 2), and the number of rows and columns of the one-dimensional chaotic sequence Y is readjusted. And a chaos-based encryption device in a body area network. The method of claim 1,
The encryption matrix combining unit combines the sub chaotic matrix Sl and the sub chaotic matrix Sk to represent a chaotic encrypted 2-dimensional chaotic matrix Ec as shown in Equation 3 below.
[Equation 3]

Reading the original image I (i, j) to form an original image data matrix T;
Constructing a Sub-Chaotic Matrix Sl, which is a sub-matrix according to a one-dimensional chaotic sequence generated by Logistic Chaotic Mapping;
Constructing a Sub-Chaotic Matrix Sk, which is a sub-matrix according to a one-dimensional chaotic sequence generated by Kent Chaotic Mapping;
Combining the sub-chaotic matrix S1 and the sub-chaotic matrix Sk to form a chaotic encrypted two-dimensional chaotic matrix Ec; And
And performing an XOR operation on the original image data matrix T and the two-dimensional chaotic matrix Ec to generate an encrypted image matrix E. Chaos based encryption method in a body domain network. The method of claim 7, wherein
Comprising the sub-chaotic matrix (Sl),
Setting an initial parameter value of X ₀ and μ according to Equation 1 below in the logistic chaotic mapping; And
Set the initial value of the iteration loop X ₀ and the parameter μ,

-Dimensional chaotic sequence with

Create it. And a readjustment of the number of rows and columns of the one-dimensional chaotic sequence X.
[Equation 1]

Where μ is a parameter for nonlinear intensity control and Xn represents the value of the state variable after the nth iteration. when [mu] [3.5699456, 4], Xn [[0, 1] and n [n] N are chaotic. The method of claim 7, wherein
Comprising the sub-chaotic matrix (Sk),
Setting initial parameter values of Y ₀ and a in Equation 2 in the kent chaos mapping; And
Sets the initial parameter value of a in iteration Y ₀ , and the encryption device is in chaotic state.

and generates a one-dimensional chaotic sequence Y = {Y ₁ , Y ₂ ..., Yn ₂ } with N ₂ = N-ceil (N / 2), and the number of rows and columns of the one-dimensional chaotic sequence Y is readjusted. Chaos-based encryption method in a body area network, comprising the step of.
[Equation 2]

Where a is a control parameter. When 0.4 <a <0.5 and Yn ∈ [0, 1], it is an ideal chaotic state.

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