Critical Reviewing AES and DES: A Comparative Analysis of Symmetric Block Ciphers

Critical Reviewing AES and DES
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Table of Contents
Table of Figures..............................................................................................................................3
Executive Summary....................................................................................................................... 4
Introduction...................................................................................................................................5
Literature Review...........................................................................................................................6
Methods and Solutions..................................................................................................................8
Experimental Analysis..................................................................................................................12
Future Scope................................................................................................................................ 13
Conclusion................................................................................................................................... 14
References................................................................................................................................... 15
Table of Figures
Figure 1 General Architecture DES Cryptographic Algorithm........................................................7
Figure 2 Hardware based implementation of AES on FPGA...........................................................8
Figure 3 Architecture of Expanded DES Algorithm.......................................................................10
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Executive Summary
In this era of e-commerce and technical advancement by introducing various types of new
technologies it is important to have security as one of the key aspects that need to be
modified and improved so that the transmission of data over insecure networks can also be
made secure and private. To protect the data of customers and clients various security
measures have been adopted. Cryptography and encryption standard is one of those
measures that aim at providing security to the data by manipulating its outer look.
The various cryptographic algorithms have been reviewed in this paper. The two main
symmetric algorithms have been discussed are Data Encryption Standard and Advanced
Encryption Standard. The first block cipher algorithm introduced for data encryption is DES
but due to its incapability, new approach and techniques are developed leading to much
new development in this area. Triple DES or 3DES is an expanded version of DES that has
been developed to overcome the faults of DES. Later, a completely new algorithm called AES
has been developed to provide better and faster security and data encryption. The process
and methodologies of both these algorithms have been discussed in detail in this paper.
Along with the process involved with both of these algorithms the paper also discusses the
faults of both the algorithms and their future scope and applications. The algorithms can be
modified in a certain way to get better results and increase its application and use in the
commercial market. Critical analysis of the use of AES and DES algorithms have been
discussed to get a better overview of the concept and get a relevant contextual reference
dealing with the complete knowledge of the topic. This era needs a better opportunity to
deal with the security issue and its data encryption techniques (Gupta¸2017).
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Introduction
Over the past years, cryptographic algorithms have been used extensively in fighting
security threats. Cryptography is the technique used to make a system secure from external
attacks. It transforms the message so that no unauthorized user can understand its meaning
and only the authorized receiver can decipher the message and get the relevant information
out of it. Secure systems are of utmost importance in recent times. Data transmission and
data storage need to be secure in all types of business. Security in systems is required from
high sensitive embedded devices to parallel computing devices for improving a system’s
overall performance. Hence, this requirement of performance enhancement has given birth
to diverse research in the field of encryption standards (Wadhwa, 2013).
One such cryptographic algorithm is Data Encryption Standard (DES) which is a block
algorithm that encrypts data in form of blocks with the help of symmetric keys such that the
same key is used for both encryption and decryption. Another cryptographic algorithm is
Advanced Encryption Standard (AES) that has been based on the symmetric key encryption
algorithm and has a huge base of applications. AES algorithm has been termed as a new
commercial algorithm that has been started to be widely used practically and commercially
in businesses and has replaced the traditional Data Encryption Standard (DES). AES has also
been known as Rijndael cipher algorithm. AES algorithm needs to be implemented as
hardware based because it is faster, secure and needs less power supply than its software-
based implementation.
The AES algorithm has been currently and widely used in the market to encrypt not only text
but also images and other forms of media. The use of Advanced Encryption Standard (AES)
has been increased with its aspect of encrypting an image. The resultant of encryption of an
image is a GIF that is not available for users to see until it has been successfully decrypted by
following a proper sequence of steps as followed during its encryption. Such innovations in
the field of data and media encryption have taken this field into a great consideration of
future scope (Gupta¸2017).
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