1. 1
A REVIEW STUDY OF CRYPTOGRAPHY TECHNIQUES
NAVDEEP KAUR1
RUCHIKA JERATH2
1M.Tech (cse) pursuing, RIMT, Mandi Gobindgarh.
2Asst. Professor, Dept. of CSE, RIMT, Mandi Gobindgarh, Punjab, India
ABSTRACT: Cryptography is a technique which
provides security to the messages sent between sender
and receiver on a network. Only authorized users can
access the message. It helps to maintain the integrity of
communication on a network. There are two main term
of cryptography which are encryption and decryption.
Encoding of message provided by Encryption and
decoding of message provided by Decryption.
Cryptography is a technique which provides security to
our data by using two methods which are substitution
and transposition encryption method. There are two
main types of cryptography schemes used one is
symmetric key cryptography which depends on single
key value and asymmetric key cryptography which
depends on pair of keys.
Keywords: Cryptography, Substitution Techniques,
Transposition Techniques, Symmetric Key
Cryptography, Asymmetric Key Cryptography.
1. INTRODUCTION
Cryptography is a technique to provide the security to
data communication in the presence of third party.
Every user wants a secure network to communicate
that data should be secure and there is no intruder can
read their data. Cryptography is used in
Wireless and wired network for providing secure data
communication. Cryptography converts the plain text
into cipher text and cipher text into a plain text. Plain
text is converted into a cipher text which is at a
sender side known as encryption and cipher text is
converted into a plain text which is at a receiver side
known as decryption.
Encryption converts readable form of message into
unreadable form. Decryption converts unreadable
form of message to readable form. Cryptography is
divided into two types’ symmetric key cryptography
and asymmetric key cryptography.
Symmetric key cryptography use single key for
encryption and decryption hence it is called as secret
key cryptography and asymmetric key use pair of
public and private key so it is called as public key
cryptography.
Cryptography services
. A service that improve the security of the data
processing systems. There are four type of services
provided by Cryptography such as confidentiality,
integrity, authentication, non-repudiation
1.1 Basics of Cryptography
Cryptography provides security to the data during the
transmission by performing some operations. The
main aim of cryptography is to help user to hide
information from unauthorized user.
1.1.1 ENCRYPTION
Encryption is a technique which is converting a
readable form of message into unreadable form
which means conversion of plain text into cipher text.
Encryption is performed when message is send by
sender. The process of encryption is shown below
fig.
fig.process of encryption

2. 2
1.1.2 DECRYPTION
It is a technique of cryptography which is converting
an unreadable form of message into readable form
which means that conversion of cipher text into a
plain text known as decryption. Decryption is
performed when message is received by receiver. The
process of decryption is shown below fig.
fig. process of decryption
2. ANALYSIS OF CRYPTORAPHICS
TECHNIQUES:
2.1 Secret Key & Public Key Cryptography
There are two keys are used in the cryptography
which is secret key (symmetric cipher) and public
key (asymmetric cipher).
2.2 SYMMETRIC KEY CRYPTOGRAPHY
It is the one type of encryption algorithm which
converts plain text into cipher text. It provides the
security of data when data is transmission from one
to another by using single secrete key. This secrete
key is same to perform encryption and decryption.
This key is known to only those users who are
sending and receiving the message on that network.
Secret key maintain the security of data therefore no
other person access the data.
Fig. process of symmetric key cryptography.
Encryption algorithm is divided into two parts:
 Block Cipher :
When messages are too long then it is difficult to
encrypt the data then block cipher overcome this
problem by the dividing the data into the fixed size of
blocks. which are maybe 64 bit or 128 bit size of
blocks. Encryption is performed on individual block
by using same key.
There are various modes of block cipher which are
Electronic Code Book (ECB), Cipher Block Chaining
(CBC), Cipher Feedback (CFB), and Output
Feedback (OFB).
 Stream Cipher
But in the stream cipher the data is encrypt within
one digit block. It does not encrypt the whole digits
within the block in one time, it encrypt only one digit
at particular one time encryption.
2.3. ASYMMETRIC KEY CRYPTOGRAPHY
It is also called as public key cryptography. Rather
than using single key for encryption and decryption
two different key are use for encryption and
decryption. Where one key encrypt and other can
decrypt. If sender sends a message then encryption is
perform on sender side by using receiver public key
and sends a message to the receiver. Only receiver
can able to see a message and receiver decrypt a
message by using receiver
Private Key so security is maintained. Here key
management is required. [1]
Fig. Process of Asymmetric Key Cryptography.

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Table.1 advantage and disadvantage of symmetric
cipher and asymmetric cipher [2]
2.4 DES (Data Encryption Standard): DES
defined as a block encryption algorithm. It was the
first encryption standard published by NIST
(National Institute of Standards and Technology). It
is a symmetric algorithm, means same key is used for
encryption and decryption. It uses one 64-bit key.
Out of 64 bits, 56 bits make up the independent key,
which determine the exact cryptography
transformation; 8 bits are used for error detection.
The main operations are bit permutations and
substitution in one round of DES. Six different
permutation operations are used both in key
expansion part and cipher part. Decryption of DES
algorithm is similar to encryption, only the round
keys are applied in reverse order. The output is a 64-
bit block of cipher text. Many attacks and methods
recorded the weaknesses of DES, which made it an
insecure block cipher key [3]
2.5. 3DES (Triple DES): 3DES is an enhancement
of Data Encryption Standard. It uses 64 bit block size
with 192 bits of key size. The encryption method is
similar to the one in the original DES but applied 3
times to increase the encryption level and the average
safe time. 3DES is slower than other block cipher
methods. [4]
2.6 AES (ADVANCED ENCRYPTION
STANDARDS)
The Advanced Encryption Standard (AES) is a
symmetric-key block cipher algorithm, U.S.
government standard for secure data and classified
data for encryption and decryption.[5]
In December 2001, the National Institute of
Standards (NIST) approved the AES as Federal
Information Processing Standards Publication (FIPS
PUB) 197, which specifies application of the
Rijndael algorithm to all sensitive classified data.[6]
The AES has three fixed 128-bit block ciphers with
cryptographic key sizes of 128, 192 and 256 bits. Key
size is unlimited, whereas the block size maximum is
256 bits. The AES design is based on a substitution-
permutation network (SPN) and does not use the
Data Encryption Standard (DES) Feistel network.[7]
The AES replaced the DES with new and updated
features:
 Block encryption implementation
 128-bit group encryption with 128, 192 and
256-bit key lengths
 Symmetric algorithm requiring only one
encryption and decryption key
 Data security for 20-30 years
 Worldwide access
 No royalties
 Easy overall implementation
2.7 RSA (Rivest-Shamir-Adleman)
RSA is a cryptosystem for public-key encryption,
and is widely used for securing sensitive data,
particularly when being sent over an insecure
network such as the Internet.
RSA was first described in 1977 by Ron Rivest, Adi
Shamir and Leonard Adleman of the Massachusetts
Institute of Technology. Public-key cryptography,
also known as asymmetric cryptography, uses two
different but mathematically linked keys, one public
and one private. The public key can be shared with
everyone, whereas the private key must be kept
secret. In RSA cryptography, both the public and the
private keys can encrypt a message; the opposite key
from the one used to encrypt a message is used to
decrypt it. This attribute is one reason why RSA has
become the most widely used asymmetric algorithm:
It provides a method of assuring the confidentiality,
integrity, authenticity and non-reputability of
electronic communications and data storage.[8]
3. CONCLUSION
In this paper I have studied about cryptographic
techniques and provide the security to data by hiding
original data. It is prevent unauthorized user to access
the data. It provide authentication to user to protect
from unauthorized user. Cryptography is a best way
for secure data. The process of encryption and
decryption is the main mechanism which is working
and guiding the flow of data.
Reference:
[1] Saykhede, A. et al. “A Survey Paper on Type and
Method of Cryptography Technique”
INTERNATIONAL JOURNAL FOR RESEARCH
E-ISSN: 2349-7610 VOLUME-2, SPECIAL ISSUE-
1, MARCH-2015
[2] http://disp.ee.ntu.edu.tw

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[3] Juneja, M. et al. “A Review of Cryptography
Techniques and Implementation of AES for Images”
International Journal of Computer Science and
Electronics Engineering (IJCSEE) Volume 1, Issue 4
(2013) ISSN 2320-401X; EISSN 2320-4028
[4] Juneja, M. et al “A Review of Cryptography
Techniques and Implementation of AES for Images”
International Journal of Computer Science and
Electronics Engineering (IJCSEE) Volume 1, Issue 4
(2013) ISSN 2320-401X; EISSN 2320-4028
[5] https://www.techopedia.com
[6] https://www.techopedia.com
[7] https://www.techopedia.com
[8] http://searchsecurity.techtarget.com