Cryptography Techniques for Network Security: A Research Project

ITC595 Research Project
Cryptographic Technique
A. Abdul
ITC595 MIT, School of Computing & Mathematics, Charles Sturt University
[e-mail]
ABSTRACT – This paper aims to research over cryptography. One
of the major problems all industries facing today is the leakage of
data. The attackers get their hands on the precious data and might
misuse it. We need to look into possible solution so that the data
does not reach in wrong hands. In this paper, we have described
certain cryptography techniques, to store data in an encrypted
form. Techniques like ciphering, MAC, Hash Function, SHA are
described in detail to get a gist of the topic.
Keywords— Cryptography; secret key; Authentication;
Confidentiality
INTRODUCTION
In the recent years, the networks trespassers have
expanded their technical knowledge, advanced superior
packages and feature determined out new approaches to take
advantage of community vulnerabilities. The activities of such
intruders can create a stampede for the companies as the
intruders can easily have access to the confidential
information of an organization. It can also harm a person
personally as an attacker can come to know the account’s
number and password and can easily misuse it according to his
own advantage. All these issues have raised the demand for
network security. Network security can be divided into four
categories: confidentiality, authentication, non-repudiation,
and integrity.
Confidentiality – Confidentiality refers to keeping the
information out of unauthorized people.
Authentication – Authentication refers to knowing whom you
are talking to before revealing sensitive information.
Nonrepudiation – Nonrepudiation deals with the digital
signature so that the other party cannot deny the authenticity
of the message (Baortaz, 2005).
Integrity – Integrity refers to ensuring that the content of the
message is not altered while sending and receiving the
message.
Figure 1 Encryption technology
For these reasons, cryptography has become an essential part
of computers and communication networks. Cryptography
protects everything from business emails to internet shopping
to electronic bank transactions.
Cryptography is the process of encrypting a plain text
(readable) into a ciphertext (non-readable) (Deffie, 1976).
Cryptography involves certain mathematical techniques to
avoid eavesdropping. The boom in the use of cryptography
can be dated back to 20th century when wireless
communication was introduced in the communication
networks. Until the early 1990s, only governmental, military
and financial data were protected by encryption. But now
things as simple as chat applications are well encrypted. There
are several ways to encrypt the valuable information like a
block cipher, stream cipher, MAC (Message Authentication
Codes), Hash Functions, Public key, Private Key, Digital
Signatures etc.
A. Research Problem
The major issue is discussed in the research report is about
to network source. To resolve this issue, the authentication
and confidentiality technique is used. This research paper is
based on the security issues which can be solved by the
cryptographic technology (Sharma, 2015).
B. Research Justification
This research aims to solve the security issues with
identifying the network issues. Research is being performed
after reviewing the research article to find the best technology
with the best result. With this research, provide the
knowledge of the cryptography technology with their
functionality.
Figure 2 Cryptography technique
TABLE I: COMPARISON OF ALGORITHM
S.
no.
Comparison
Cryptography Size Generation time
1

Algorithm
1 DES 56 29
2 RSA 1024 287
3 AES 128 75
4 ElGamal 160 86
This given table shows the comparison between the
cryptography algorithms with their generation time.
LITERATURE REVIEW
Cryptography is an emerging technology. It refers to
encrypting a text in a manner that it becomes non-readable.
Cryptanalysis refers to the process of decrypting the ciphertext
into the plain text. The process of encryption and decryption
of data is called cryptology.
Plain Text – Plain text refers to the original text that can be
read by humans (Sharma, 2015).
Cipher Text – Ciphertext is the encrypted or the secret text
that contains a certain amount of redundancy so to make it
non-readable.
Fig 1: Cryptology
Where E: Encryption, D: Decryption, C.T: Cipher Text, P.T:
Plain Text.
C. Cryptosystems
Generally, cryptosystems are divided into two categories:
Symmetric Cryptosystems and Asymmetric Cryptosystems
based on the keys used in encryption and decryption
processes.
In Symmetric Cryptosystems, the keys used in encryption and
decryption are both identical or are derived from each other.
The key should be kept secret otherwise the secure
communication can be compromised. The disadvantage of this
system is that it creates a key distribution problem which is
handled in asymmetric cryptosystems. An example of
symmetric cryptosystem is DES (Data Encryption Standard).
In Asymmetric Cryptosystems, the keys used for encryption
and decoding are dissimilar. The key for encryption is kept
secret and the decryption key is kept secret. If user M1 wants
to send M2 a message then he can encipher it using the public
key of M2. M2 can decipher the text using his private key
(Gaubatz, 2005).
Figure 3 Cryptographic algorithm
D. Symmetric Cryptosystems
This section mainly focuses on symmetric cryptosystem
techniques: stream ciphers, block ciphers, MAC algorithm,
Hash Functions etc.
It is the encryption procedure that encodes a fixed magnitude
block of n-bits of facts. The size of the data blocks can be 64
bits, 128 bits, and 256 bits. A block cipher drives intake 64-bits
of normal text and will generate a ciphertext of 64-bits. The
popular block ciphers used today are DES, AES, 3DES, Blowfish,
Two fish. Based on the approach of action, the block cipher is
divided into two categories: Deterministic and Probabilistic
(Patil, 2013).
Electronic Code Block (ECB) – It is the most used methods in
the ciphering processes. It is a deterministic mode of
operation. In this method, each message is divided into
numerous blocks and formerly all block is encrypted
separately. It is very fast.
Figure 4 Block Diagram of CB
Cipher Block Chaining (CBC) – In this method, all the blocks
are made dependent on the previous block for encryption.
Cipher Feedback (CFB) – It is same as CBC.
Offset Code Block (OCB) – It is a block mode of cipher for
operations that offers authentication and confidentiality
parallel at the identical time.
DES (Data Encryption Standard) – It is an encryption
procedure for electronic information. DES is capable to deliver
a security with high level and is easy to understand. It is
available to all users and is easy to use (Gaubatz, 2005).
Advanced Encryption Standard [AES] - It is the symmetric
algorithm for block cipher that has been implemented in
software and hardware worldwide to protect sensitive data.
AES comprises three block ciphers: AES-192, AES-128, and
AES-256. All cipher encodes and decrypts the data packets in
blocks of 128 bits by means of the cryptology algorithm.
A stream cipher is an encrypting algorithm that encrypts bits
and bytes of plaintext at a time. Since 1980s additive stream
ciphers have been used in cryptography due to its low
implementation cost. In a stream cipher, a small key and an
initialization value (IV) are appended to a plain text and they
are encrypted [6]. The key is the stream of pseudorandom
bits. Stream Ciphers are also called One-Time Pad which
means that it uses a random key which is unpredictable and it
is used only once. The only problem with this algorithm is that
a key must be as lengthy as or equal to the length of the plain
text. This cipher is not used for day-to-day use but is
warranted in matters of national security. A popular stream
cipher is RC4.
RC4 – It has been invented to encrypt software on the 8-bit
machine. It is currently being implemented in SSL/TSL
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E D
P. C. P.T