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Chaotic Cuttle Fish Algorithm for Feature
Selection of Intrusion Detection System 1V.R. Balasaraswathi,
2M. Sugumaran and
3Yasir Hamid
1Department of Computer Science & Engineering,
Pondicherry Engineering College, Pondicherry, India.
[email protected] 2Department of Computer Science & Engineering,
Pondicherry Engineering College, Pondicherry, India. 3Department of Computer Science & Engineering,
Pondicherry Engineering College, Pondicherry, India.
Abstract As usage of computer grows hastily, masses of data have been generated
in almost all the fields and security also becomes the most important need
to protect the data and network. The generated data is extremely large and
it is very difficult to extract knowledge from it. Feature Selection (FS) is a
perpetual method used to select the efficient and relevant features and also
reduces the dataset size. Since FS is a complex task in extracting the
important features in data mining, many heuristic algorithms were used for
FS. Cuttle Fish Algorithm (CFA) is a metaheuristic algorithm which works
based on colour changing behaviour of cuttlefish used to solve optimisation
problems. Chaotic Cuttle Fish Algorithm (CCFA) is proposed to select the
important and non redundant features for Intrusion Detection System
(IDS). In view of the fact that random number plays important role in CFA,
Choatic map is used in CCFA to generate random number sequence.
Experimental results and analysis shows the performance of CCFA has
been improved by chaotic random sequences.
Key Words:Cuttle fish algorithm, choatic map, heuristic algorithm,
feature selection, intrusion detection system.
International Journal of Pure and Applied MathematicsVolume 119 No. 10 2018, 921-935ISSN: 1311-8080 (printed version); ISSN: 1314-3395 (on-line version)url: http://www.ijpam.euSpecial Issue ijpam.eu
921
1. Introduction
Recently security becomes must in all the networking domains. IDS is a
software to detect the intruders entering into a network (Smaha, Stephen E,
1988). The detected activity is informed to the administrator (Depren, Ozgur, et
al., 2005). Most commonly IDS is classified into Network Intrusion Detection
Systems (NIDS) and Host Based Intrusion Detection Systems (HIDS)
(Zhengbing, Hu, Li Zhitang, and Wu Junqi, 2008)(E. Biermann, E. Cloete, and
L. M. Venter, 2001). Network traffic is monitored and analyzed by NIDS. HIDS
monitors and analyze the host system.
Traditional algorithms do not produce better results for complex optimisation
problems. Now a day’s enormous bio-inspired heuristic algorithm are emerging
to solve optimisation problems (Baghel, Malti, Shikha Agrawal, and Sanjay
Silakari, 2012). Bio-inspired are based on individual behavior or collective
behavior of swarms. Ant Colony Optimisation (ACO), Firefly Algorithm,
Particle Swarm Optimisation (PCO), Bat Algorithm (BA), Artificial Bee Colony
Algorithm (ABC), Genetic Programming etc were used in various fields to solve
real time as well as complex Engineering problems(Dressler, Falko, and Ozgur
B. Akan, 2010). The applications of bio-inspired algorithms are feature
selection, feature extraction, segmentation, scheduling, control systems, routing,
etc(Yang, Xin-She, et al., 2013).
Metaheuristic algorithms have been used in an all the fields (Yang, Xin-She,
2010). Chaotic systems generate excellent random number sequence
(Thompson, John Michael Tutill, and H. Bruce Stewart, 2002). Recently,
parameters in metaheuristic algorithms are replaced by chaotic sequences in
order to fine tune it(Sheikholeslami, R., and A. Kaveh, 2013).The parameters of
BA, PSO, Firefly, Bee colony etc have been replaced by chaotic
sequences(Fister, Iztok, Matjaž Perc, and Salahuddin M. Kamal,
2015),(Afrabandpey, Homayun, et al., 2014),(Alatas, Bilal, 2010)(Kuang,
Fangjun, et al., Springer). Chaotic sequences improve the performance of the
algorithm since the solution generated has higher mobility and multiplicity.
Section 2 describes about the related work of FS. Section 3 gives the
introduction of chaotic maps and different types of maps. Section 4 explains the
Chaotic Cuttle Fish algorithm and its pseudocode. Section 5 described about the
KDD99 Dataset used. Section 6 illustrates the experimental analysis and section
7 gives the conclusion.
2. Related Work
FS is the process of extracting the best set of features from the entire set (Jain,
Anil, and Douglas Zongker, 1997). Instead of using entire feature set for
constructing a model, it is enough to use relevant and significant features to
build a model (Guyon, Isabelle, and André Elisseeff, 2003). FS is used in almost
International Journal of Pure and Applied Mathematics Special Issue
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all the fields to reduce the dataset size (Weston, Jason, et al., 2001) and reduces
training time and evaluation time. FS also improves accuracy and overall
performance. Two methods of FS are filter, wrapper and hybrid method (Das,
Sanmay, 2001). The filter is a traditional method which does not use any
classifier for evaluation. Evaluation is done by some measures like dependency,
correlation, distance, similarity etc. Wrapper method uses classifier for
evaluation. To improve the performance, filter and wrapper method are
combined and it is called as hybrid method.
Many traditional methods were used for FS. Principal Component Analysis
(PCA) is used to select the relevant features (Xin Xu and Xuening Wang, 2005)
and Support Vector Machine (SVM) is used for classification. The binary
gravitational search algorithm is combined with mutual information for FS of
IDS (Bostani, Hamid, and Mansour Sheikhan, 2017). Gaussian SVM with
Pulse-Coupled Neural Network algorithm (PCNN) performs better(Shrivastava,
Aditya, Mukesh Baghel, and Hitesh Gupta, 2013). Linear Discriminant Analysis
(LDA)(Tan, Zhiyuan, et al., 2010) is also used. Features are selected by
calculating attribute ratio (Chae, Hee-su, et al., 2013) and it gives better
accuracy.
Evolutionary algorithms are also used for FS of IDS. A genetic algorithm is
used for selecting important features(Stein, Gary et al., 2005).GA is also
combined with PCA (Iftikhar Ahmad, Azween B Abdulah et al., 2011), Kernel
PCA(Kuang, Fangjun, Weihong Xu, and Siyang Zhang, 2014) and
SVM(Aslahi-Shahri, B. M., et al., 2016). A combination of GA with PCA,
Kernel PCA and SVM performs well when compared with traditional methods.
Recently bio-inspired algorithms are also used for FS of IDS. These algorithms
performed well in terms of accuracy, detection rate, and error rate. PSO (Wang,
Jun, et al., 2009) and the combination of PSO with SVM (Tian, Jiang, and Hong
Gu, 2010) gives high detection rate and accuracy. Bee algorithm is also used for
selecting more relevant features(Alomari, Osama, and Zulaiha Ali Othman,
2012).Membrane computing concept is used with Bee algorithm in order to
improvise its performance (Rufai, Kazeem I., RavieChandren Muniyandi, and
Zulaiha A. Othman, 2014). Ant colony algorithm with SVM as classifier
produces less alarm rate (Xingzhu, Wang, 2015).CFA is a metaheuristic
algorithm used for FS gives better performance.
3. Chaotic Maps
Chaos was introduced by Lorenz in the year 1963 (E.N.Lorenz, 1963). Chaos is
modeled by chaotic maps (González, Jorge A., and Ramiro Pino, 1999).
Randomness is obtained by probability distributions in metaheuristic algorithms.
The randomness can be replaced by chaotic maps since it has better randomness
with dynamical and statistical properties. Chaotic Optimization (CO) is a
method of replacing random variables with chaotic maps (Stojanovski, Toni,
and Ljupco Kocarev,2001). Chaotic maps have two properties such as stochastic
International Journal of Pure and Applied Mathematics Special Issue
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and ergodicity. One –dimensional map are given below.
Logistic Map
Robert May introduced logistic map in the year of 1976(Phatak, S. C., and S.
Suresh Rao, 1995). It is defined as
Iterative Map
Iterative map is defined as
)
Sine Map
Where 0 < a ≤ 4
Sinusoidal Map
It is defined as
Circle Map
It is defined (DeGuzman, G. C., and J. AS Kelso, 1991) as
+ b –
Where a = 0.5 and b = 0.2
Chebyshev Map
It is defined as
= cos
Gauss/Mouse Map
The Gaussian map was written by Gauss in 1825 and published in 1827(Ruh,
Ernst A, and Jaak Vilms, 1970). It is defined as
Singer Map
It is a one-dimensional map defined as
Where a = 7.86, b = 23.31, c = 28.75 and s = 13.3
Where lies between 0.9 and 1.08.
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Arnold’s Cat Map
It was introduced by Vladimir Arnold in the year 1960 using cat’s image
(Peterson, Gabriel , 1997). It is defined as
xn and yn
Henon Map
It was introduced by Michel Henon (Grassberger, P., H. Kantz, and U. Moenig,
1989). It is defined as
Where a =1.4 and b=0.3.
4. Chaotic Cuttle Fish Algorithm for
Feature Selection of IDS
CFA is a metaheuristic algorithm works based on the color changing behavior
(Eesa, Adel Sabry, Adnan Mohsin Abdulazeez Brifcani, and Zeynep Orman,
2013). Cuttlefish changes its color based on its environment using different
layers of skin (Hanlon, Roger T and Messenger, John B, 1988). Reflection and
visibility are the two parameters used in it. The algorithm contains six cases
(Eesa, Adel Sabry, Zeynep Orman, and Adnan Mohsin, 2015) and the six cases
are grouped into four steps. The six cases are based on the stretch and shrinking
of three layers of skin such as iridophores, chromatophores and leucophores.
Figure 1: Shows Skin Layers of Cuttlefish
Figure 2: Shows 6 Cases of Colo
Changing Behavio
Initialisation
The initial population is formed by using Chebyshev chaotic maps from the
entire dataset randomly from the whole dataset. The ranking is done for the
features. Each population is connected with selected feature set and unselected
feature set. Fitness is calculated for each population using fitness function given
International Journal of Pure and Applied Mathematics Special Issue
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below.
Where α ϵ [0, 1], β = 1-α
Both detection rate and false positive rate is important, consider α = 0.5, β = 0.5.
If only detection rate is important consider α = 0.5, β = 0.3
After fitness is calculated, each population is evaluated using j48 Decision Tree
(DT) classifier. The best solution is kept in BS and AVBS.
Table 1
S.No Parameters Meaning
1 A Total number of population
2 BS Best subset of all the subsets
3 AVBS Average best subset among the subsets
4 SFS Size of the selected features set
6 USFS Size of the unselected features set
7 Sf Set of the selected features
8 USfs Set of the unselected features
9 RS Subset formed randomly
10 NS Newly formed subset
11 REF Reflection degree
12 VIS Visibility degree
13 rn Reflection
14 vy Visibility
15 Pi Individual Population
Case 1, 2
The population is sorted and best kl populations are taken randomly from (1,
A/2).
KL=random (A/2)
Where KL is a random number generated between 0 and A/2.
kl is calculated and selected randomly by using logistic map from total
population.
For each population rn and vy (subsets with REF and VIS elements) is calculated
to obtain NS.REF and rn are calculated from Sf. VIS and vy are calculated from
USf.
rn = RS[REF] from pi..Sf (2)
vy = RS[VIS] from pi..USf (3)
REF = γ (0, SFS) (4)
VIS = δ (0, USFS) (5)
NS =rn +vy (6)
Where γ and δ are chaotic random sequences generated by Gauss and henon’s
chaotic maps.
REF is nothing but reflection degree which helps to calculate the stretch and
shrink interval and VIS is the ultimate view of the corresponding pattern.
International Journal of Pure and Applied Mathematics Special Issue
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Case 3,4
Iridhophores cells reflect the incoming colour. Reflected colour is considered as
the removal of one feature from the Sf. A single feature is chosen from USfs
randomly.
rn = Sfs of BS – Sfs of BS[REF] (7)
vy = USfs of BS[VIS] (8)
REF = ε (0, size of Sfs of BS) (9)
VIS =δ (0, size of USfs of BS) (10)
Where ε and ζ are chaotic random sequences generated by sine and sinusoidal
chaotic maps.
The NS is calculated from equation (6)
Case 5
The light which comes from the chromatophores is similar to outgoing light
since leucophores acts as a mirror. A feature which is removed from SFS is vy.
rn = AVBS – Sfs (11)
vyi = AVBS – Sfs[i] (12)
Where i = {1, 2,...,REF} (13)
NSi = rn - vyi (14)
Case 6
The new solution is obtained from incoming color since leucophores reflect
the incoming color. The random solution is generated by circle map from the
population kl to A. NS is obtained from kl to A population.
Pseudocode of CCFA 1. Initial population P [A] is formed with subsets randomly.
2. J48 Decision Tree (DT) is used to evaluate the population fitness and rank the
population.
3. The best solution is placed in AVBS and BS (Remove one feature).
4. Repeat until stopping criteria is met
1. Case 1, 2
Population is sorted based on the fitness
Find kl = random (A/2)
For i = 0 to kl
{
vy and rn is calculated from Eq.(2) and(3)
REF and VIS is calculated from Eq. (4) and (5)
NS is calculated from Eq.(6)
NS is evaluated by j48 classifier
if( NS is better than AVBS)
Assign NS as AVBS
}
2. Case 3, 4
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For i = 0 to n
{
Using BS one feature is exchanged randomly between Sf and USf to form NS.
NS is evaluated by j48 classifier
if (NS is better than BS)
Assign NS as BS
}
3. Case 5
For i = 0 to AVBS.SFS
{
NS is created by removing i feature from AVBS
NS is evaluated by j48 classifier
If (NS is better than BS)
Assign NS as BS
}
4. Case 6
For i = kl to A
{
New population Pi is generated using A-kl
NS is generated randomly
NS is evaluated using j48 classifier
If (NS is better than Pi)
Assign NS as Pi
If (Pi is better than AVBS)
Assign Pi as AVBS
}
5. End
6. Return BS
5. KDD99 Dataset
A group of Lincoln Laboratories at MIT University was generated called
KDD99 Dataset (Cup, K. D. D., 2007). It is a simulation of connections and data
transfer over a military network. The dataset is of 4GB in size and contains 5
million connections. It contains normal and four different attacks such as Denial
of Service (DOS), Probe, Remote to Local (R2L) and User to Root (U2R)
attacks. Dataset is grouped into training and testing datasets. The dataset
contains 41 different features and the features were classified into basic, content,
intrinsic and traffic features. Many IDS researchers are using this dataset for
classifier evaluation
6. Experimental Results and Analysis
The KDDCUP99 dataset is used for evaluation of chaotic CFA (CCFA)
algorithm. The algorithm is implemented on Dual core CPU,1 GB RAM and
windows operating system. The experiment is done for a various subset of
features and results are given for various performance measures. The results of
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CFA and CCFA are shown in the table 1.CCFA comparatively performs much
better than CFA.
Table 2: Illustrates the Experimental Results o CFA and CCFA
S.No Number of Features
Fitness Computation Time (sec) Detection Rate Accuracy False Positive Rate
CFA CCFA CFA CCFA CFA CCFA CFA CCFA CFA CCFA
1 41 74.45 79.01 0.31 0.28 71.08 77.26 73.26 80.5 17.8 14.33
2 33 78.01 83.33 0.25 0.20 69.5 82.18 75.1 84.26 2.20 2.008
3 25 83.62 87.55 0.20 0.17 78.21 84.21 81.71 88.25 3.75 3.332
4 18 92.15 92.54 0.16 0.12 91.10 92.8 92.2 93.66 3.40 3.212
5 12 93.18 95.66 0.11 0.1 92.4 96.4 92.55 96.01 3.77 3.51
Figure 3: Shows Fitness of CFA and CCFA
Figure 4: Shows Computation Time of CFA and CCFA
Figure 5: Shows Detection Rate of CFA and CCFA
International Journal of Pure and Applied Mathematics Special Issue
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Figure 6: Show Accuracy of CFA and CCFA
Figure 7: Shows False Positive Rate of CFA and CCFA
7. Conclusion
In this paper, the proposed chaotic CFA shows how the color changing the
behavior of cuttlefish helps in selecting best features for IDS.A six different
chaotic maps have been used to acclimatize the CFA parameters. The
randomness of CFA is improved by using the chaotic random sequences Chaotic
CFA improves the performance of CFA in terms of accuracy, detection rate,
computation time and false alarm rate. Chaotic random number sequence in
CFA enhances the global search of CFA algorithm. The chaotic random
sequences in CCFA select the efficient, relevant and non-repeated features to
enhance the performance of IDS. The chaotic random sequences can be used in
bio-inspired and heuristic algorithms where randomness and ergodicity plays an
important role.
Acknowledgment
This work was supported by the University Grants Commission under Rajiv
Gandhi National Fellowship for SC students.
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