SlideShare a Scribd company logo
IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 387
SECURITY ANALYSIS OF FBDK BLOCK CIPHER FOR DIGITAL
IMAGES
M. Kiran Reddy1
, K. J. Jegadish Kumar2
1
M.E-Communication Systems, 2
Assistant Professor, Electronics and Communication Department, SSN College of
Engineering, Tamilnadu, India
Abstract
Network security is one of the major concerns in the modern world. In this regard, a strong security technique is required to protect
user data. Cryptography techniques plays an important role in secured transmission through encryption of data and thus ensuring
integrity, authenticity, confidentiality of information. Several encryption algorithms have been proposed like AES (Advanced
Encryption Standard), DES (Data Encryption Standard) and RSA. These provide very good encryption for text applications. However,
these encryption schemes appear not to be ideal for image applications. Some algorithms like GKSBC and RC6 provide very good
encryption for digital images. New techniques are emerging that are aimed at providing secured transmission of images over
networks. The FBDK (Fixed Block with Dynamic Key Size) block cipher is a new cryptography technique designed using simple
operations like XOR, substitutions, circular shifting. The FBDK algorithm is applicable for blocks of any size with key size being
dynamic for each block. It does not involve any complex mathematical operations like modular exponentiation. It is a hybrid
cryptography technique based on symmetric key and asymmetric key cryptosystems. This paper investigates the security of FBDK
block cipher for digital images against brute-force attack, statistical analysis and Differential analysis attacks. In this paper, various
security analysis tests has been discussed which are helpful in finding out whether the FBDK encryption algorithm can do secure
encryption or not. Experimental results proves the security and efficiency of FBDK cipher for images against all aforementioned
types of attacks which justifies its consideration for real time image applications.
Keywords: Cryptography, Ciphers, Encryption, Security, and cryptanalysis.
----------------------------------------------------------------------***------------------------------------------------------------------------
1. INTRODUCTION
The security of digital images is more important since the
communication of digital products over open networks occur
more and more frequently. Special and efficient technique is
needed for storage and transmission of data securely.
Encryption is the most practical security technique for digital
data in computer systems.
In order to fulfill such a task, many encryption methods have
been proposed such as DES, AES and RSA. However, these
encryption schemes appear not to be ideal for image
applications, due to bulk data capacity and high redundancy.
Also, they involve complex mathematical calculations that
require more time. In [2], FBDK block cipher was proposed,
which is capable of handling any block size with dynamic key
size based on the size of the message. The design procedure of
the FBDK algorithm is given in detail in [2]. This paper
explores the security of FBDK algorithm regarding brute
force, statistical attacks and Differential analysis in secured
transmission of digital images. The experiments carried out
along with their outcomes are discussed in detail in the
following sections.
2. SECURITY ANALYSIS AND TEST RESULTS
A good encryption technique has thoroughly rearranged pixel
positions, values transformed and visually transformed
processes. Some security analysis parameters [1] which are
done on FBDK algorithm are:
1. Statistical analysis
2. Key space analysis
3. Encryption quality
4. Differential analysis
2.1 Statistical Analysis
Shannon introduced two methods known as diffusion and
confusion which will make intruders and their attackers more
bewildered [1]. Diffusion means spreading out the influence of
a single plain image pixel over many cipher image pixels.
Confusion means, using transformations that Complicate the
dependence of statistics of the cipher image on the statistics of
the plain image [1]. The statistical analysis test is done by
finding out histogram and correlation of encrypted image with
respect to original image. The tests were performed using
Microsoft Windows 2008 on Intel(R) core(TM) i3-2350 CPU,
2.3 GHz to 2 GB of RAM using Matlab 7.0.
IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 388
2.1.1 Histogram
These are the first visual test performed by the intruders as
well as sender and receiver while decryption [1]. The
histogram of original and encrypted image must totally be
different, so that no sort of information about the original
image can be obtained from the encrypted image. Figure 1
shows the histograms of the original image “Cameraman.tif”
and its encrypted image. From the figure 1 it can be seen that
the histogram of encrypted image is completely different from
that of the original image and hence the FBDK algorithm is
highly resistant to histogram analysis and intruder can gain no
information from the encrypted image through visual tests.
Fig -1: Histogram analysis using FBDK algorithm. (a)
Original Image, (b) Histogram of Original Image, (c)
Encrypted Image, (d) Histogram of Encrypted Image.
2.1.2 Correlation Coefficient
Correlation coefficient gives the degree of similarity or
relationship between original and encrypted images [7]. Let A
be the original image and B be the encrypted image of size
MXN. Then the correlation coefficient denoted by ϓ is
calculated as,
ϓ =
 



m m n
mmn
n
mmn
m n
mmnmmn
BBAA
BBAA
))(
2
())(
2
(
))((
Where, Amn is pixel intensity at mth
row and nth
column of
original image, Bmn is pixel intensity at mth
row and nth
column
of encrypted image. Am is mean of all elements in original
image A and Bm is mean of all elements in encrypted image B.
The table 1 shows the correlation coefficient values obtained
for various images encrypted using FBDK algorithm.
Table -1: Correlation coefficient of standard Images
encrypted with FBDK algorithm
Image Size ϓ
Singer.jpg 256X256 -0.0005
Lena.tif 512X512 -0.0022
Pirage.tif 512X512 0.0006
The range of ϓ is -1 to +1. If the correlation coefficient value
is close to -1 or +1 then the original and encrypted images are
highly correlated and a significant information about original
image can be easily obtained from encrypted image. If ϓ is
close to zero then the original image and encrypted image are
highly uncorrelated and this implies the encryption efficiency
is high. From Table 1 the ϓ values obtained by encrypting
various standard images are very low (nearly zero) which
indicates that the original image and encrypted image are
highly uncorrelated and hence statistical attacks using
correlation is very difficult. The results of Histogram analysis
and Correlation coefficient tests prove that the FBDK
algorithm is highly resistant to statistical attacks. In the next
section, the algorithm’s resistance to key space analysis is
investigated.
2.2 Key Space Analysis
The key space refers to the number of bits used to encrypt
image. The key size should be large enough to tackle key
space analysis also known as brute force search attack. Here,
all possible key combinations are tried on the encrypted
message. Suppose, if the original key length used by the
receiver is of N bits, then 2N
combinations of key are possible.
If the N is very large, then it will be very difficult for the
attacker to try all the combinations. In the worse case, the
minimum number of searches the intruder must perform in
order to get the original key should be 2N/2
. The security of an
algorithm depends on its resistance to brute force search. The
proposed algorithm is analyzed against brute force search and
the experimental results prove it to be more resistant to key
space analysis. The table 1 shows the brute force search time
required with different N values and at an average decryption
time of 2.456. In the proposed algorithm the key length varies
for each block and hence it is very difficult for the attacker to
know the key length and to perform key analysis. Since, the
text and image data is highly encrypted and there is no pattern
of input seen in the encrypted output, the proposed algorithm
is also resistant to traffic analysis and release of message
content attacks.
IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 389
Table -2: Brute Force search analysis of FBDK algorithm
Key Length (in bits) Brute Force search time
(years)
128 5.61e+36
136 5.28e+38
144 1.29e+41
152 3.36e+43
The table 2 shows that if a key of length 128 bits is used then
the time required to perform brute for search is 5.61e+36
years. This is very large when compared with the lifetime of
the message that is being transmitted. Hence proposed
algorithm is highly resistant to brute force search attack or key
space analysis.
2.3 Encryption Quality
A good encryption scheme must posses high encryption
quality and low execution time [7]. In this section, encryption
quality and performance analysis tests were conducted on
FBDK algorithm using text and image files. The tests were
performed using Microsoft Windows 2008 on Intel(R)
core(TM) i3-2350 CPU, 2.3 GHz to 2 GB of RAM using
Matlab 7.0.
2.3.1 Encryption Analysis
To determine the encryption quality two tests Viz., EQ
measure, and PSNR (Peak Signal to Noise Ratio) value
calculation is performed.
2.3.1.1 Encryption Quality (EQ) measure
When an image is encrypted there will be a change in its grey
scale values. The EQ [7] measure gives the amount of
deviation of grey scale values in original and encrypted
images. Let I denote the original image and I’ denote the
encrypted image each of size M*N pixels with L grey levels.
Let HL(I) denote the number of occurrences of each grey level
L in the original image and HL(I’) denote the number of
occurrences of each grey level L in the encrypted image. The
encryption quality [7] represents the average number of
changes to each grey level L and is expressed mathematically
as,
Encryption Quality = 256
)()'(
255
0


L
LL IHIH
The table 3 gives a comparison between GKSBC and FBDK
in terms of EQ. All the images are of size 512X512 and FBDK
has high EQ values compared to GKSBC [7]. Hence, the
proposed algorithm proves to be efficient for image encryption
when compared with GKSBC.
Table -3: EQ comparison between GKSBC and FBDK
Image File EQ (GKSBC) EQ (FBDK)
Lena (512X512) 663.82 714.65
Baboon (512X512) 773.90 823.71
Girl (512X512) 894.89 939.71
2.3.1.2 PSNR Value
An efficient encryption algorithm produces an unintelligible
image [3] as output. The parameter that can be used for
determining the encryption efficiency of the algorithm is the
PSNR (peak signal to noise ratio) [4] value in decibels (dB).
Ideally, PSNR value between the actual image and encrypted
image (PSNR_A_E) should be 0 dB and between the actual
image and decrypted image (PSNR_A_D) it should be infinity
[7]. Practically an efficient algorithm give a PSNR value less
than 9 dB between actual image and encrypted image, a PSNR
value between (30-60) dB between actual image and
decrypted image. Table 2 shows the PSNR values obtained
with various standard test images taken as input to the
proposed algorithm. For all the images the PSNR value is
quite good, this also indicates that the algorithm can tolerate
various statistical attacks like the traffic analysis,
autocorrelation analysis etc. The PSNR values for decrypted
image show that the original image can be reconstructed
efficiently from the encrypted image.
Table -4: PSNR values for different Standard test images
encrypted using FBDK
Image name Dimensions PSNR_A_E
(dB)
PSNR_A_D
(dB)
Cameraman.tif 256 X 256 8.389 37.8532
Singer.jpg 225 X 225
X 3
8.6653 46.9137
Pirate.tif 512 X 512 8.9183 36.6502
2.4 Differential Analysis
Generally, the intruder tries to make slight changes such as
modifying one pixel of the encrypted image, and then
observes the change of the result. After such changes, if the
attacker is able to obtain any relevant information about
original image from the encrypted image then the algorithm
used for encryption is practically inefficient. Also, the
encrypted image must be sensitive to small changes in original
image. If a change in original image can cause a significant
change in the cipher image with respect to diffusion and
confusion, then the differential attack becomes very inefficient
on that image. The methods [1] used to study the influence of
one-pixel change on the whole image, encrypted by FBDK
are: Number of Pixels Change Rate (NPCR) and Unified
Average changing Intensity (UACI). NPCR gives the number
of pixels change rate in encrypted image when one pixel
IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 390
change occurs in original image [1]. Consider two encrypted
images T1 and T2, whose original images have only one pixel
difference. Then, NPCR of two images is defined as [1]:
NPCR=
%100*
*
),(
,
vw
jiS
ji

Where, S (i, j) = 




),(),(if,1
),(),(if,0
21
21
jiTjiT
jiTjiT
w=number of rows in an image, v=number of columns in an
image, (i,j)=Position of Pixels
Another method, UACI is unified average changing intensity
which measures the average intensity of differences between
original image and ciphered image [1]. The formula for UACI
is:
UACI =
%100*
255
),(),((
*
1
,
21


ji
jiTjiT
vw
NPCR or UACI are random variables dependent on
parameters such as the image size and format of image rather
than statistical values. For UACI the typical value taken on an
average for different image sizes is 34% and for NPCR score
the upper bound is 100% (ideal value) which indicates, it is
difficult to establish relationship between the images. One
performed test is on the one-pixel change influence on a 256
grey-scale image “cameraman.tif” of size 256X256. The
Figure 2 (b) shows the encrypted image and figure 2 (c) shows
the encrypted image obtained after one pixel value in the
original image is changed. The NPCR and UACI values for
different image sizes are listed in Table 5.
Fig -2: (a) Original Image, (b) Encrypted Image, (c) Encrypted
Image after pixel value change.
The encrypted images before and after pixel change are
completely scrambled. There is no significant information
about the original image is available in these images. From
table 5, we can find the values of NPCR and UACI to be very
close to ideal value for all size of images. This indicates that
no sort of relationship can be established between the
encrypted images.
Table 5 NPCR and UACI values for images of different sizes
encrypted with FBDK
Size NPCR UACI
128X128 99.2432% 33.254%
256X256 99.2523% 33.384%
512X512 99.3147% 33.462%
The NPCR and UACI tests prove that the FBDK algorithm is
resistant to differential analysis and hence it can be used
efficiently for digital image encryption for secured
transmission through the communication networks. Also, the
clearance of the differential analysis tests indicates that the
algorithm is also resistant to attacks like chosen plaintext,
chosen ciphertext, traffic analysis.
3. CONCLUSIONS
In modern communication world, image encryption plays a
crucial role, and hence, an efficient encryption algorithm is
necessary. The paper provides encryption efficiency analysis
and security evaluation of FBDK algorithm. The various
security analysis tests shows that FBDK block cipher can be
considered to be a real-time encryption technique for digital
images.
ACKNOWLEDGEMENTS
The authors wish to express heartful thanks to the faculty of
ECE, SSN College of Engineering, Chennai for their support
to this research.
REFERENCES
[1]. Taranjit Kaur, Reecha Sharma, “Security Definite
parameters for image encryption techniques”, International
journal of Emerging Technology and Advanced Engineering,
Volume 3, Issue 5, May, 2013.
[2]. M.Kiran Reddy and K.J.Jegadish Kumar,
“Implementation of Novel Hybrid Cryptography Algorithm”,
In press.
[3]. M. Ashwak AL-Abiachi, Faudziah Ahmad, Ku Ruhana, “
A Competitive Study of Cryptography Techniques over block
cipher”, UKSim 13th International Conference on Modelling
and Simulation, 2011.
[4]. Amitesh Singh Rajput, Nishchol Mishra, Sanjeev Sharma,
“Towards the Growth of Image Encryption and Authentication
Schemes”, International Conference on Advances in
IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308
_______________________________________________________________________________________
Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 391
Computing, Communicactions and Informatics (ICACCI),
2013.
[5]. G. Chen, Y. Mao and C.K. Chui, “A symmetric image
encryption scheme based on 3D chaotic cat maps”, Chaos
Solitons Fractals 2004; 21:749-61, 2004.
[6]. Nitty Sarah Alex and L. Jani Anbarasi, “Enhanced Image
Secret Sharing via Error Diffusion in Halftone Visual
Cryptography”, IEEE International Conference on ICASSP,
1985.
[7]. S. Arul jothi and M. Venkatesulu, “Encryption Quality
and Performance analysis of GKSBC algorithm”, Journnal of
Information Engineering and Applications, vol 2, No.10,
2012.
BIOGRAPHIES
M.Kiran Reddy is currently pursuing his
Masters degree in communication systems
in SSN Collegeof Engineering,
Email-id: kiran.reddy889@gmail.com
K.J.Jegadish Kumar is working as
Assistant Professor in SSN college of
Engineering, Chennai in ECE Department.
Email-id: jegadishkj@ssn.edu.in

More Related Content

What's hot (20)

PDF
Image and text Encryption using RSA algorithm in java
PiyushPatil73
 
PDF
Secure Data Storage on Cloud System for Privacy Preserving
IRJET Journal
 
PDF
ijircee_Template
ijircee
 
PDF
Ijcnc050208
IJCNCJournal
 
PDF
Secrecy and Performance Analysis of Symmetric Key Encryption Algorithms
Tharindu Weerasinghe
 
PPT
Rsa Encryption in java
PiyushPatil73
 
PDF
Comparison of Secret Splitting, Secret Sharing and Recursive Threshold Visual...
TELKOMNIKA JOURNAL
 
PDF
Mj3422172221
IJERA Editor
 
PDF
Enhanced Efficient & Secure Steganography Algorithm with Low Distortion
IRJET Journal
 
DOC
File transfer using cryptography techniques
miteshkumar82
 
PDF
RSA 32-bit Implementation Technique
Universitas Pembangunan Panca Budi
 
PDF
Advanced Encryption Standard (AES) Implementaion using Java
Sunil Kumar R
 
PDF
C0281010016
inventionjournals
 
PPT
Encryption
shyam Tirkey
 
PDF
Comparative study of private and public key cryptography algorithms a survey
eSAT Publishing House
 
PDF
Time Performance Analysis of RSA and Elgamal Public Key Cryptosystems
ijtsrd
 
PDF
Iaetsd a survey on cloud storage security with
Iaetsd Iaetsd
 
PDF
A new hybrid text encryption approach over mobile ad hoc network
IJECEIAES
 
PPT
An Approach on Data Security with the Combination of Symmetric and Asymmetric...
AnirbanBhowmik8
 
PDF
Design and implementation of hierarchical visual
IJNSA Journal
 
Image and text Encryption using RSA algorithm in java
PiyushPatil73
 
Secure Data Storage on Cloud System for Privacy Preserving
IRJET Journal
 
ijircee_Template
ijircee
 
Ijcnc050208
IJCNCJournal
 
Secrecy and Performance Analysis of Symmetric Key Encryption Algorithms
Tharindu Weerasinghe
 
Rsa Encryption in java
PiyushPatil73
 
Comparison of Secret Splitting, Secret Sharing and Recursive Threshold Visual...
TELKOMNIKA JOURNAL
 
Mj3422172221
IJERA Editor
 
Enhanced Efficient & Secure Steganography Algorithm with Low Distortion
IRJET Journal
 
File transfer using cryptography techniques
miteshkumar82
 
RSA 32-bit Implementation Technique
Universitas Pembangunan Panca Budi
 
Advanced Encryption Standard (AES) Implementaion using Java
Sunil Kumar R
 
C0281010016
inventionjournals
 
Encryption
shyam Tirkey
 
Comparative study of private and public key cryptography algorithms a survey
eSAT Publishing House
 
Time Performance Analysis of RSA and Elgamal Public Key Cryptosystems
ijtsrd
 
Iaetsd a survey on cloud storage security with
Iaetsd Iaetsd
 
A new hybrid text encryption approach over mobile ad hoc network
IJECEIAES
 
An Approach on Data Security with the Combination of Symmetric and Asymmetric...
AnirbanBhowmik8
 
Design and implementation of hierarchical visual
IJNSA Journal
 

Viewers also liked (17)

PDF
Proximate composition of seeds of hybrid varieties of minor millets
eSAT Journals
 
PDF
Implementation of adaptive stft algorithm for lfm signals
eSAT Journals
 
PDF
Automatic detection and severity analysis of brain tumors using gui in matlab
eSAT Journals
 
PDF
An evaluation of jute epoxy-hybrid composite materials for automotive frontal...
eSAT Journals
 
PDF
Static analysis of c s short cylindrical shell under internal liquid pressure...
eSAT Journals
 
PDF
Effect of basic pretreatment on saccharification of water hyacinth
eSAT Journals
 
PDF
Factors influencing the rise of house price in klang valley
eSAT Journals
 
PDF
Gsm or x10 based scada system for industrial automation
eSAT Journals
 
PDF
Voice operated wheel chair
eSAT Journals
 
PDF
Web cam sensing using sdk tool
eSAT Journals
 
PDF
Growth, structural and optical studies of pure and kbr doped adp crystals
eSAT Journals
 
PDF
Comparative analysis of improved high performance direct power control of thr...
eSAT Journals
 
PDF
Microcontroller based smart wear for driver safety
eSAT Journals
 
PDF
Mechanical properties of bio mineralized concrete
eSAT Journals
 
PDF
Swing, voltage stability and power transfer capability in transmission system...
eSAT Journals
 
PDF
Multiple adsorption of heavy metal ions in aqueous solution using activated c...
eSAT Journals
 
PDF
Productivity improvement through lean deployment & work study methods
eSAT Journals
 
Proximate composition of seeds of hybrid varieties of minor millets
eSAT Journals
 
Implementation of adaptive stft algorithm for lfm signals
eSAT Journals
 
Automatic detection and severity analysis of brain tumors using gui in matlab
eSAT Journals
 
An evaluation of jute epoxy-hybrid composite materials for automotive frontal...
eSAT Journals
 
Static analysis of c s short cylindrical shell under internal liquid pressure...
eSAT Journals
 
Effect of basic pretreatment on saccharification of water hyacinth
eSAT Journals
 
Factors influencing the rise of house price in klang valley
eSAT Journals
 
Gsm or x10 based scada system for industrial automation
eSAT Journals
 
Voice operated wheel chair
eSAT Journals
 
Web cam sensing using sdk tool
eSAT Journals
 
Growth, structural and optical studies of pure and kbr doped adp crystals
eSAT Journals
 
Comparative analysis of improved high performance direct power control of thr...
eSAT Journals
 
Microcontroller based smart wear for driver safety
eSAT Journals
 
Mechanical properties of bio mineralized concrete
eSAT Journals
 
Swing, voltage stability and power transfer capability in transmission system...
eSAT Journals
 
Multiple adsorption of heavy metal ions in aqueous solution using activated c...
eSAT Journals
 
Productivity improvement through lean deployment & work study methods
eSAT Journals
 
Ad

Similar to Security analysis of fbdk block cipher for digital images (20)

PPTX
Biometric Hashing technique for Authentication
AnIsh Kumar
 
PDF
Secure Image Encryption Using Filter Bank and Addition Modulo 28 with Exclusi...
CSCJournals
 
DOCX
Image encryption using aes key expansion
Sreeda Perikamana
 
PDF
A Novel Approach Using Advanced Encryption Standard to Implement Hard Disk Se...
IJNSA Journal
 
PDF
Development and performance comparison of modified RSA algorithm with other c...
IRJET Journal
 
PDF
AN ENHANCED CHAOTIC IMAGE ENCRYPTION
ijcseit
 
PDF
Image encryption approach for security issues
IAEME Publication
 
PDF
Image encryption
rakshit2105
 
PPTX
Image Security System using Image Processing
SruthiReddy112
 
PPTX
Image Security
Satyendra Rajput
 
PDF
An Advance Approach of Image Encryption using AES, Genetic Algorithm and RSA ...
IJEACS
 
PDF
Efficient Fpe Algorithm For Encrypting Credit Card Numbers
IOSR Journals
 
PDF
Cryptanalysis of image encryption using traditional encryption tecnhniques
Ritwik MG
 
PDF
IMAGE ENCRYPTION TECHNIQUES USING FRACTAL FUNCTION: A REVIEW
ijcsit
 
PDF
Image Encryption Techniques Using Fractal Function : A Review
AIRCC Publishing Corporation
 
PDF
Image Encryption Techniques Using Fractal Function : A Review
AIRCC Publishing Corporation
 
PDF
PSEUDO RANDOM KEY GENERATOR USING FRACTAL BASED TRELLIS CODED GENETIC ALGORIT...
IJNSA Journal
 
PDF
DESIGN AND ANALYSIS OF A NOVEL DIGITAL IMAGE ENCRYPTION SCHEME
IJNSA Journal
 
PDF
Survey on Different Image Encryption Techniques with Tabular Form
ijsrd.com
 
PPTX
Image encryption using aes key expansion
Sreeda Perikamana
 
Biometric Hashing technique for Authentication
AnIsh Kumar
 
Secure Image Encryption Using Filter Bank and Addition Modulo 28 with Exclusi...
CSCJournals
 
Image encryption using aes key expansion
Sreeda Perikamana
 
A Novel Approach Using Advanced Encryption Standard to Implement Hard Disk Se...
IJNSA Journal
 
Development and performance comparison of modified RSA algorithm with other c...
IRJET Journal
 
AN ENHANCED CHAOTIC IMAGE ENCRYPTION
ijcseit
 
Image encryption approach for security issues
IAEME Publication
 
Image encryption
rakshit2105
 
Image Security System using Image Processing
SruthiReddy112
 
Image Security
Satyendra Rajput
 
An Advance Approach of Image Encryption using AES, Genetic Algorithm and RSA ...
IJEACS
 
Efficient Fpe Algorithm For Encrypting Credit Card Numbers
IOSR Journals
 
Cryptanalysis of image encryption using traditional encryption tecnhniques
Ritwik MG
 
IMAGE ENCRYPTION TECHNIQUES USING FRACTAL FUNCTION: A REVIEW
ijcsit
 
Image Encryption Techniques Using Fractal Function : A Review
AIRCC Publishing Corporation
 
Image Encryption Techniques Using Fractal Function : A Review
AIRCC Publishing Corporation
 
PSEUDO RANDOM KEY GENERATOR USING FRACTAL BASED TRELLIS CODED GENETIC ALGORIT...
IJNSA Journal
 
DESIGN AND ANALYSIS OF A NOVEL DIGITAL IMAGE ENCRYPTION SCHEME
IJNSA Journal
 
Survey on Different Image Encryption Techniques with Tabular Form
ijsrd.com
 
Image encryption using aes key expansion
Sreeda Perikamana
 
Ad

More from eSAT Journals (20)

PDF
Mechanical properties of hybrid fiber reinforced concrete for pavements
eSAT Journals
 
PDF
Material management in construction – a case study
eSAT Journals
 
PDF
Managing drought short term strategies in semi arid regions a case study
eSAT Journals
 
PDF
Life cycle cost analysis of overlay for an urban road in bangalore
eSAT Journals
 
PDF
Laboratory studies of dense bituminous mixes ii with reclaimed asphalt materials
eSAT Journals
 
PDF
Laboratory investigation of expansive soil stabilized with natural inorganic ...
eSAT Journals
 
PDF
Influence of reinforcement on the behavior of hollow concrete block masonry p...
eSAT Journals
 
PDF
Influence of compaction energy on soil stabilized with chemical stabilizer
eSAT Journals
 
PDF
Geographical information system (gis) for water resources management
eSAT Journals
 
PDF
Forest type mapping of bidar forest division, karnataka using geoinformatics ...
eSAT Journals
 
PDF
Factors influencing compressive strength of geopolymer concrete
eSAT Journals
 
PDF
Experimental investigation on circular hollow steel columns in filled with li...
eSAT Journals
 
PDF
Experimental behavior of circular hsscfrc filled steel tubular columns under ...
eSAT Journals
 
PDF
Evaluation of punching shear in flat slabs
eSAT Journals
 
PDF
Evaluation of performance of intake tower dam for recent earthquake in india
eSAT Journals
 
PDF
Evaluation of operational efficiency of urban road network using travel time ...
eSAT Journals
 
PDF
Estimation of surface runoff in nallur amanikere watershed using scs cn method
eSAT Journals
 
PDF
Estimation of morphometric parameters and runoff using rs & gis techniques
eSAT Journals
 
PDF
Effect of variation of plastic hinge length on the results of non linear anal...
eSAT Journals
 
PDF
Effect of use of recycled materials on indirect tensile strength of asphalt c...
eSAT Journals
 
Mechanical properties of hybrid fiber reinforced concrete for pavements
eSAT Journals
 
Material management in construction – a case study
eSAT Journals
 
Managing drought short term strategies in semi arid regions a case study
eSAT Journals
 
Life cycle cost analysis of overlay for an urban road in bangalore
eSAT Journals
 
Laboratory studies of dense bituminous mixes ii with reclaimed asphalt materials
eSAT Journals
 
Laboratory investigation of expansive soil stabilized with natural inorganic ...
eSAT Journals
 
Influence of reinforcement on the behavior of hollow concrete block masonry p...
eSAT Journals
 
Influence of compaction energy on soil stabilized with chemical stabilizer
eSAT Journals
 
Geographical information system (gis) for water resources management
eSAT Journals
 
Forest type mapping of bidar forest division, karnataka using geoinformatics ...
eSAT Journals
 
Factors influencing compressive strength of geopolymer concrete
eSAT Journals
 
Experimental investigation on circular hollow steel columns in filled with li...
eSAT Journals
 
Experimental behavior of circular hsscfrc filled steel tubular columns under ...
eSAT Journals
 
Evaluation of punching shear in flat slabs
eSAT Journals
 
Evaluation of performance of intake tower dam for recent earthquake in india
eSAT Journals
 
Evaluation of operational efficiency of urban road network using travel time ...
eSAT Journals
 
Estimation of surface runoff in nallur amanikere watershed using scs cn method
eSAT Journals
 
Estimation of morphometric parameters and runoff using rs & gis techniques
eSAT Journals
 
Effect of variation of plastic hinge length on the results of non linear anal...
eSAT Journals
 
Effect of use of recycled materials on indirect tensile strength of asphalt c...
eSAT Journals
 

Recently uploaded (20)

PPTX
Heart Bleed Bug - A case study (Course: Cryptography and Network Security)
Adri Jovin
 
PDF
MAD Unit - 1 Introduction of Android IT Department
JappanMavani
 
PPTX
Green Building & Energy Conservation ppt
Sagar Sarangi
 
PDF
Ethics and Trustworthy AI in Healthcare – Governing Sensitive Data, Profiling...
AlqualsaDIResearchGr
 
PPTX
Hashing Introduction , hash functions and techniques
sailajam21
 
PDF
International Journal of Information Technology Convergence and services (IJI...
ijitcsjournal4
 
PDF
Introduction to Productivity and Quality
মোঃ ফুরকান উদ্দিন জুয়েল
 
PPTX
Introduction to Design of Machine Elements
PradeepKumarS27
 
PDF
GTU Civil Engineering All Semester Syllabus.pdf
Vimal Bhojani
 
PPTX
Innowell Capability B0425 - Commercial Buildings.pptx
regobertroza
 
DOCX
8th International Conference on Electrical Engineering (ELEN 2025)
elelijjournal653
 
PDF
6th International Conference on Machine Learning Techniques and Data Science ...
ijistjournal
 
PPTX
MPMC_Module-2 xxxxxxxxxxxxxxxxxxxxx.pptx
ShivanshVaidya5
 
PPTX
Day2 B2 Best.pptx
helenjenefa1
 
PPTX
Types of Bearing_Specifications_PPT.pptx
PranjulAgrahariAkash
 
PPTX
265587293-NFPA 101 Life safety code-PPT-1.pptx
chandermwason
 
PPTX
Lecture 1 Shell and Tube Heat exchanger-1.pptx
mailforillegalwork
 
PPTX
Pharmaceuticals and fine chemicals.pptxx
jaypa242004
 
PDF
Water Design_Manual_2005. KENYA FOR WASTER SUPPLY AND SEWERAGE
DancanNgutuku
 
DOCX
CS-802 (A) BDH Lab manual IPS Academy Indore
thegodhimself05
 
Heart Bleed Bug - A case study (Course: Cryptography and Network Security)
Adri Jovin
 
MAD Unit - 1 Introduction of Android IT Department
JappanMavani
 
Green Building & Energy Conservation ppt
Sagar Sarangi
 
Ethics and Trustworthy AI in Healthcare – Governing Sensitive Data, Profiling...
AlqualsaDIResearchGr
 
Hashing Introduction , hash functions and techniques
sailajam21
 
International Journal of Information Technology Convergence and services (IJI...
ijitcsjournal4
 
Introduction to Productivity and Quality
মোঃ ফুরকান উদ্দিন জুয়েল
 
Introduction to Design of Machine Elements
PradeepKumarS27
 
GTU Civil Engineering All Semester Syllabus.pdf
Vimal Bhojani
 
Innowell Capability B0425 - Commercial Buildings.pptx
regobertroza
 
8th International Conference on Electrical Engineering (ELEN 2025)
elelijjournal653
 
6th International Conference on Machine Learning Techniques and Data Science ...
ijistjournal
 
MPMC_Module-2 xxxxxxxxxxxxxxxxxxxxx.pptx
ShivanshVaidya5
 
Day2 B2 Best.pptx
helenjenefa1
 
Types of Bearing_Specifications_PPT.pptx
PranjulAgrahariAkash
 
265587293-NFPA 101 Life safety code-PPT-1.pptx
chandermwason
 
Lecture 1 Shell and Tube Heat exchanger-1.pptx
mailforillegalwork
 
Pharmaceuticals and fine chemicals.pptxx
jaypa242004
 
Water Design_Manual_2005. KENYA FOR WASTER SUPPLY AND SEWERAGE
DancanNgutuku
 
CS-802 (A) BDH Lab manual IPS Academy Indore
thegodhimself05
 

Security analysis of fbdk block cipher for digital images

  • 1. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________ Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 387 SECURITY ANALYSIS OF FBDK BLOCK CIPHER FOR DIGITAL IMAGES M. Kiran Reddy1 , K. J. Jegadish Kumar2 1 M.E-Communication Systems, 2 Assistant Professor, Electronics and Communication Department, SSN College of Engineering, Tamilnadu, India Abstract Network security is one of the major concerns in the modern world. In this regard, a strong security technique is required to protect user data. Cryptography techniques plays an important role in secured transmission through encryption of data and thus ensuring integrity, authenticity, confidentiality of information. Several encryption algorithms have been proposed like AES (Advanced Encryption Standard), DES (Data Encryption Standard) and RSA. These provide very good encryption for text applications. However, these encryption schemes appear not to be ideal for image applications. Some algorithms like GKSBC and RC6 provide very good encryption for digital images. New techniques are emerging that are aimed at providing secured transmission of images over networks. The FBDK (Fixed Block with Dynamic Key Size) block cipher is a new cryptography technique designed using simple operations like XOR, substitutions, circular shifting. The FBDK algorithm is applicable for blocks of any size with key size being dynamic for each block. It does not involve any complex mathematical operations like modular exponentiation. It is a hybrid cryptography technique based on symmetric key and asymmetric key cryptosystems. This paper investigates the security of FBDK block cipher for digital images against brute-force attack, statistical analysis and Differential analysis attacks. In this paper, various security analysis tests has been discussed which are helpful in finding out whether the FBDK encryption algorithm can do secure encryption or not. Experimental results proves the security and efficiency of FBDK cipher for images against all aforementioned types of attacks which justifies its consideration for real time image applications. Keywords: Cryptography, Ciphers, Encryption, Security, and cryptanalysis. ----------------------------------------------------------------------***------------------------------------------------------------------------ 1. INTRODUCTION The security of digital images is more important since the communication of digital products over open networks occur more and more frequently. Special and efficient technique is needed for storage and transmission of data securely. Encryption is the most practical security technique for digital data in computer systems. In order to fulfill such a task, many encryption methods have been proposed such as DES, AES and RSA. However, these encryption schemes appear not to be ideal for image applications, due to bulk data capacity and high redundancy. Also, they involve complex mathematical calculations that require more time. In [2], FBDK block cipher was proposed, which is capable of handling any block size with dynamic key size based on the size of the message. The design procedure of the FBDK algorithm is given in detail in [2]. This paper explores the security of FBDK algorithm regarding brute force, statistical attacks and Differential analysis in secured transmission of digital images. The experiments carried out along with their outcomes are discussed in detail in the following sections. 2. SECURITY ANALYSIS AND TEST RESULTS A good encryption technique has thoroughly rearranged pixel positions, values transformed and visually transformed processes. Some security analysis parameters [1] which are done on FBDK algorithm are: 1. Statistical analysis 2. Key space analysis 3. Encryption quality 4. Differential analysis 2.1 Statistical Analysis Shannon introduced two methods known as diffusion and confusion which will make intruders and their attackers more bewildered [1]. Diffusion means spreading out the influence of a single plain image pixel over many cipher image pixels. Confusion means, using transformations that Complicate the dependence of statistics of the cipher image on the statistics of the plain image [1]. The statistical analysis test is done by finding out histogram and correlation of encrypted image with respect to original image. The tests were performed using Microsoft Windows 2008 on Intel(R) core(TM) i3-2350 CPU, 2.3 GHz to 2 GB of RAM using Matlab 7.0.
  • 2. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________ Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 388 2.1.1 Histogram These are the first visual test performed by the intruders as well as sender and receiver while decryption [1]. The histogram of original and encrypted image must totally be different, so that no sort of information about the original image can be obtained from the encrypted image. Figure 1 shows the histograms of the original image “Cameraman.tif” and its encrypted image. From the figure 1 it can be seen that the histogram of encrypted image is completely different from that of the original image and hence the FBDK algorithm is highly resistant to histogram analysis and intruder can gain no information from the encrypted image through visual tests. Fig -1: Histogram analysis using FBDK algorithm. (a) Original Image, (b) Histogram of Original Image, (c) Encrypted Image, (d) Histogram of Encrypted Image. 2.1.2 Correlation Coefficient Correlation coefficient gives the degree of similarity or relationship between original and encrypted images [7]. Let A be the original image and B be the encrypted image of size MXN. Then the correlation coefficient denoted by ϓ is calculated as, ϓ =      m m n mmn n mmn m n mmnmmn BBAA BBAA ))( 2 ())( 2 ( ))(( Where, Amn is pixel intensity at mth row and nth column of original image, Bmn is pixel intensity at mth row and nth column of encrypted image. Am is mean of all elements in original image A and Bm is mean of all elements in encrypted image B. The table 1 shows the correlation coefficient values obtained for various images encrypted using FBDK algorithm. Table -1: Correlation coefficient of standard Images encrypted with FBDK algorithm Image Size ϓ Singer.jpg 256X256 -0.0005 Lena.tif 512X512 -0.0022 Pirage.tif 512X512 0.0006 The range of ϓ is -1 to +1. If the correlation coefficient value is close to -1 or +1 then the original and encrypted images are highly correlated and a significant information about original image can be easily obtained from encrypted image. If ϓ is close to zero then the original image and encrypted image are highly uncorrelated and this implies the encryption efficiency is high. From Table 1 the ϓ values obtained by encrypting various standard images are very low (nearly zero) which indicates that the original image and encrypted image are highly uncorrelated and hence statistical attacks using correlation is very difficult. The results of Histogram analysis and Correlation coefficient tests prove that the FBDK algorithm is highly resistant to statistical attacks. In the next section, the algorithm’s resistance to key space analysis is investigated. 2.2 Key Space Analysis The key space refers to the number of bits used to encrypt image. The key size should be large enough to tackle key space analysis also known as brute force search attack. Here, all possible key combinations are tried on the encrypted message. Suppose, if the original key length used by the receiver is of N bits, then 2N combinations of key are possible. If the N is very large, then it will be very difficult for the attacker to try all the combinations. In the worse case, the minimum number of searches the intruder must perform in order to get the original key should be 2N/2 . The security of an algorithm depends on its resistance to brute force search. The proposed algorithm is analyzed against brute force search and the experimental results prove it to be more resistant to key space analysis. The table 1 shows the brute force search time required with different N values and at an average decryption time of 2.456. In the proposed algorithm the key length varies for each block and hence it is very difficult for the attacker to know the key length and to perform key analysis. Since, the text and image data is highly encrypted and there is no pattern of input seen in the encrypted output, the proposed algorithm is also resistant to traffic analysis and release of message content attacks.
  • 3. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________ Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 389 Table -2: Brute Force search analysis of FBDK algorithm Key Length (in bits) Brute Force search time (years) 128 5.61e+36 136 5.28e+38 144 1.29e+41 152 3.36e+43 The table 2 shows that if a key of length 128 bits is used then the time required to perform brute for search is 5.61e+36 years. This is very large when compared with the lifetime of the message that is being transmitted. Hence proposed algorithm is highly resistant to brute force search attack or key space analysis. 2.3 Encryption Quality A good encryption scheme must posses high encryption quality and low execution time [7]. In this section, encryption quality and performance analysis tests were conducted on FBDK algorithm using text and image files. The tests were performed using Microsoft Windows 2008 on Intel(R) core(TM) i3-2350 CPU, 2.3 GHz to 2 GB of RAM using Matlab 7.0. 2.3.1 Encryption Analysis To determine the encryption quality two tests Viz., EQ measure, and PSNR (Peak Signal to Noise Ratio) value calculation is performed. 2.3.1.1 Encryption Quality (EQ) measure When an image is encrypted there will be a change in its grey scale values. The EQ [7] measure gives the amount of deviation of grey scale values in original and encrypted images. Let I denote the original image and I’ denote the encrypted image each of size M*N pixels with L grey levels. Let HL(I) denote the number of occurrences of each grey level L in the original image and HL(I’) denote the number of occurrences of each grey level L in the encrypted image. The encryption quality [7] represents the average number of changes to each grey level L and is expressed mathematically as, Encryption Quality = 256 )()'( 255 0   L LL IHIH The table 3 gives a comparison between GKSBC and FBDK in terms of EQ. All the images are of size 512X512 and FBDK has high EQ values compared to GKSBC [7]. Hence, the proposed algorithm proves to be efficient for image encryption when compared with GKSBC. Table -3: EQ comparison between GKSBC and FBDK Image File EQ (GKSBC) EQ (FBDK) Lena (512X512) 663.82 714.65 Baboon (512X512) 773.90 823.71 Girl (512X512) 894.89 939.71 2.3.1.2 PSNR Value An efficient encryption algorithm produces an unintelligible image [3] as output. The parameter that can be used for determining the encryption efficiency of the algorithm is the PSNR (peak signal to noise ratio) [4] value in decibels (dB). Ideally, PSNR value between the actual image and encrypted image (PSNR_A_E) should be 0 dB and between the actual image and decrypted image (PSNR_A_D) it should be infinity [7]. Practically an efficient algorithm give a PSNR value less than 9 dB between actual image and encrypted image, a PSNR value between (30-60) dB between actual image and decrypted image. Table 2 shows the PSNR values obtained with various standard test images taken as input to the proposed algorithm. For all the images the PSNR value is quite good, this also indicates that the algorithm can tolerate various statistical attacks like the traffic analysis, autocorrelation analysis etc. The PSNR values for decrypted image show that the original image can be reconstructed efficiently from the encrypted image. Table -4: PSNR values for different Standard test images encrypted using FBDK Image name Dimensions PSNR_A_E (dB) PSNR_A_D (dB) Cameraman.tif 256 X 256 8.389 37.8532 Singer.jpg 225 X 225 X 3 8.6653 46.9137 Pirate.tif 512 X 512 8.9183 36.6502 2.4 Differential Analysis Generally, the intruder tries to make slight changes such as modifying one pixel of the encrypted image, and then observes the change of the result. After such changes, if the attacker is able to obtain any relevant information about original image from the encrypted image then the algorithm used for encryption is practically inefficient. Also, the encrypted image must be sensitive to small changes in original image. If a change in original image can cause a significant change in the cipher image with respect to diffusion and confusion, then the differential attack becomes very inefficient on that image. The methods [1] used to study the influence of one-pixel change on the whole image, encrypted by FBDK are: Number of Pixels Change Rate (NPCR) and Unified Average changing Intensity (UACI). NPCR gives the number of pixels change rate in encrypted image when one pixel
  • 4. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________ Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 390 change occurs in original image [1]. Consider two encrypted images T1 and T2, whose original images have only one pixel difference. Then, NPCR of two images is defined as [1]: NPCR= %100* * ),( , vw jiS ji  Where, S (i, j) =      ),(),(if,1 ),(),(if,0 21 21 jiTjiT jiTjiT w=number of rows in an image, v=number of columns in an image, (i,j)=Position of Pixels Another method, UACI is unified average changing intensity which measures the average intensity of differences between original image and ciphered image [1]. The formula for UACI is: UACI = %100* 255 ),(),(( * 1 , 21   ji jiTjiT vw NPCR or UACI are random variables dependent on parameters such as the image size and format of image rather than statistical values. For UACI the typical value taken on an average for different image sizes is 34% and for NPCR score the upper bound is 100% (ideal value) which indicates, it is difficult to establish relationship between the images. One performed test is on the one-pixel change influence on a 256 grey-scale image “cameraman.tif” of size 256X256. The Figure 2 (b) shows the encrypted image and figure 2 (c) shows the encrypted image obtained after one pixel value in the original image is changed. The NPCR and UACI values for different image sizes are listed in Table 5. Fig -2: (a) Original Image, (b) Encrypted Image, (c) Encrypted Image after pixel value change. The encrypted images before and after pixel change are completely scrambled. There is no significant information about the original image is available in these images. From table 5, we can find the values of NPCR and UACI to be very close to ideal value for all size of images. This indicates that no sort of relationship can be established between the encrypted images. Table 5 NPCR and UACI values for images of different sizes encrypted with FBDK Size NPCR UACI 128X128 99.2432% 33.254% 256X256 99.2523% 33.384% 512X512 99.3147% 33.462% The NPCR and UACI tests prove that the FBDK algorithm is resistant to differential analysis and hence it can be used efficiently for digital image encryption for secured transmission through the communication networks. Also, the clearance of the differential analysis tests indicates that the algorithm is also resistant to attacks like chosen plaintext, chosen ciphertext, traffic analysis. 3. CONCLUSIONS In modern communication world, image encryption plays a crucial role, and hence, an efficient encryption algorithm is necessary. The paper provides encryption efficiency analysis and security evaluation of FBDK algorithm. The various security analysis tests shows that FBDK block cipher can be considered to be a real-time encryption technique for digital images. ACKNOWLEDGEMENTS The authors wish to express heartful thanks to the faculty of ECE, SSN College of Engineering, Chennai for their support to this research. REFERENCES [1]. Taranjit Kaur, Reecha Sharma, “Security Definite parameters for image encryption techniques”, International journal of Emerging Technology and Advanced Engineering, Volume 3, Issue 5, May, 2013. [2]. M.Kiran Reddy and K.J.Jegadish Kumar, “Implementation of Novel Hybrid Cryptography Algorithm”, In press. [3]. M. Ashwak AL-Abiachi, Faudziah Ahmad, Ku Ruhana, “ A Competitive Study of Cryptography Techniques over block cipher”, UKSim 13th International Conference on Modelling and Simulation, 2011. [4]. Amitesh Singh Rajput, Nishchol Mishra, Sanjeev Sharma, “Towards the Growth of Image Encryption and Authentication Schemes”, International Conference on Advances in
  • 5. IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 _______________________________________________________________________________________ Volume: 03 Issue: 02 | Feb-2014, Available @ http://www.ijret.org 391 Computing, Communicactions and Informatics (ICACCI), 2013. [5]. G. Chen, Y. Mao and C.K. Chui, “A symmetric image encryption scheme based on 3D chaotic cat maps”, Chaos Solitons Fractals 2004; 21:749-61, 2004. [6]. Nitty Sarah Alex and L. Jani Anbarasi, “Enhanced Image Secret Sharing via Error Diffusion in Halftone Visual Cryptography”, IEEE International Conference on ICASSP, 1985. [7]. S. Arul jothi and M. Venkatesulu, “Encryption Quality and Performance analysis of GKSBC algorithm”, Journnal of Information Engineering and Applications, vol 2, No.10, 2012. BIOGRAPHIES M.Kiran Reddy is currently pursuing his Masters degree in communication systems in SSN Collegeof Engineering, Email-id: [email protected] K.J.Jegadish Kumar is working as Assistant Professor in SSN college of Engineering, Chennai in ECE Department. Email-id: [email protected]