Cryptography, Cryptography And Decryption Keys Essay

Cryptography, Cryptography And Decryption Keys Essay
Chapter: 4 Summary Basically there are two hiding techniques and those are Cryptography and Steganography.
In cryptography an encryption and decryption keys will be available for encoding and decoding purpose
respectively and it is having triple key to provide secured data to the receiver safely. Now in steganography not
only encryption and decryption are to be done but there is cover media to provide more security and that is
known as chaotic image encryption. Steganography is providing four layer security to the user and it supports
media like audio files, video files, images etc. Will be there. Hence by combining these two methods we can
have more security. For the encryption purpose we need to understand substitution and permutation. Now
substitution is the method in which there will be mapping of another value and in Permutation there will be
reordering of every bit position of every input we have given. Now firstly the steganography was traced back to
440 BC when Herodotus did show his two examples in his histories. Demaratus sent a warning about
forthcoming attack to Greece by writing it directly and also wax tablets were used as reusable writing and
sometimes it's used for shorthand. Now we also introduced Non linearity's to encryption and decryption both as
wee know the rounds are generated
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Statement Of Purpose For Cryptography
"An algorithm that resists brute force will never become obsolete, no matter how powerful code–breaking
computers get. It would become a world standard overnight." This quote from Dan Brown's Digital Fortress
caught my imagination in high school, and from that point onwards, I knew that this is what I wanted to do. I
wanted to become a research scientist, who would decipher such algorithms, even more so break a cipher
claimed to be perfect. Since then I have been studying cryptography, which led to a tendency of seeing patterns
and codes in my daily activities. Routine activities such as reading a letter or looking at a sign, trigger
connections in my mind. I have always enjoyed reading theorems and understanding their proofs. My interest in
cryptography further burgeoned since every protocol, or algorithm ... Show more content on Helpwriting.net ...
UCSD is the school of my choice as I find that the graduate program is fully suited to my interests and
ambitions. I have always admired Dr. Mihir Bellare's work on designing protocols, and efficient encryption
schemes, which gave me a deep insight in the field of searchable encryption. It would be a privilege to work
under him and contribute to the field under his tutelage. Driven by my interest in Cryptography, I will be
delighted to join the Security and Cryptography group at UCSD and play an active role in their research.
Besides research I also have an inclination towards teaching, since interpersonal communication and clarity of
speech are my forte. Having had the experience of tutoring students online on the InstaEDU forum, working as
a Teaching Assistant would come naturally to me. Adding up my research interests, penchant for teaching, and
interest in ongoing projects, I strongly believe that UCSD would be the ideal platform to kick start my career in

Cryptography, The Science Of Study And Practice
Q1.
A
Cryptography is the science of study and practice of various techniques related to secure communications by
means of adversaries. The study deals with analysis of various techniques and constructing protocols to block
the adversaries. Aspects like non–repudiation, integrity of data are important to modern day cryptography.
Modern day cryptography utilizes Computer science, and mathematics disciplines and its applications span for
the usage of ATM cards, distribution systems encryption and in the areas of electronic commerce (1, 2).
b. Public key cryptography is one of the commonly used methods for protecting information available over
web. It is a type of cryptography techniques that utilizes a legacy public key algorithm ... Show more content on
Helpwriting.net ...
Important encryption algorithms used are DES, AES and 3DES. These algorithms are capable of performing
with a high encryption speed there are symmetric and asymmetric encryptions. Their modes of operation for
block cipher encryption use a varieties of methods and techniques such as Electronic Codebook Mode, Output
Feedback mode and Chain Block chaining modes. Blowfish is also one of the commonly used encryption
algorithms and there was no recorded report of attack successful since its inception and that it assures a good
security base for the information (5)
E
Substitution cipher is a procedure of encoding where cipher content replaces a plain text units. In a substitution
cipher, the units of the plaintext are held in the same succession in the cipher text, but the units themselves are
modified. There are various distinctive substitution ciphers and keys for the straightforward substitution ciphers
normally comprise of 26 letters (8).
Below is a case key example
Plain letter set: abcdefghijklmnopqrstuvwxyz
Figure letter set: phqgiumeaylnofdxjkrcvstzwb
Case utilizing the above key
Plaintext: guard the east mass of the palace
Cipher text: giuifg cei iprc tpnn du cei qprcni
Q2.
a. What is Role Based Access Control (RBAC)? Define and describe with examples.
It is a process of access control which controls users to access their destined roles and authorizations. They may
be based on the basis of name of

A Note On The And Cryptography Essay
PROJECT #1
(Cracking A Vigenere Cipher)
SUBMITTED TO: Dr.Huapeng Wu Course number:06–88–566–01 Course name:Data Security and
Cryptography University of Windsor Windsor, Ontario
SUBMITTED BY: Amanbir Singh Seth Student ID:104655731 Masters of Engineering in Electrical and
Computer Engineering University of Windsor Windsor, Ontario
2
DATA SECURITY AND CRYPTOGRAPHY
OBJECTIVE OF PROJECT:
For a given piece of cipher text generated with a vigenere cipher, find its encryption key and recover the
corresponding plaintext.
ASSIGNED CIPHER TEXT:
FCQUKTSCOWRCQUZKEPLKIBGUGUHELWIUUOSDYCUVAOTHUAUUACFBGKCALDLWZANVQ
WYFPHUMCCSDSQYRUHCYMXIERDDIDHPXSCUMANJLFAZVOSPIQYYQSUPBFBKZDMMUHUQ
QQBZPZKAWFQGZHMLGKOFIPLOZIVOSDVNHBWFAWCULQAVMXYHZWYFVJQLVVHTYOHBFY
NWWQWGOSIUUVIFQCYRXSEHZYVWAWZIVPQQXJPGTUPKGIBKJVRLQTZAHIMCDWGVTTUD
PHIYTLAQWJHBUWCSZKMVYOUAJASZCPNHTYUWWXFXHGQMQUHTYOHBFYNWWQWGDSD
YUOOWCPNJUINLBFFAZSQBGYSUNYHGXCMLHTCUOSEUKKOFFCZHFBGYSIUUZCYYVOWZAK
UHTUVJOEYUVAQJKLQQIHLJUXGUQQMNPUTNKUWFMGSTBYTOOBMDBHENKSZQHQBUTIH
HQXOGACOIPUSONVOSYOTKSDYTDWFBVOSOLKTSUNYHGHCVHZFIJPAFBCAWFMJVIXXDLRQ
MVYCKYFISRITLWFQCZRUMEVJQLGKOZXKAGECIUWRCEHBOYCWDDYEPOFYFAVQLGMCDYJL
HAIMAVQLKZYFBGNFQUVYWEEQMQAGKUUUHJLFQZKURUHIAVQWCZSXIERSPBGDOEIDSWS
YFACRITJSUNVOIEVGAFMSKUUTCUWFQMGUQQZQYVUGVVHMEGAVMNTPGWCVTIENJHJQ
VGLBEIOLHTCPNCRATLOFCOWCDNCUQQVWAKTUVDOECVHVOLKLRBIKYCFQKAVMAGZHGL
GVTMHILFFBCAWPIPVHWHQDOPIEBAQHVVTEIOLYUHFDWFBQBHPIWIHBIUZWNFAAVQMEY
OBIHWOBYTKCDWCZGMQKUVQLJHBPSGZHQLFHMMZVLFZIQUOZXKOWEUPNSDVWYGFZQY

Annotated Bibliography On Encryption And Cryptography
Contents
1 Cryptography 2
Introduction 2
Methods of encryption or cryptography. 2
Symmetric 2
Asymmetric 2
Operation and Working of Both Methods 3
Ingredients of symmetric encryption 3
Working of symmetric cryptography (Graphical Representation) 4
Ingredients of Asymmetric cryptography 4
Working principal of Asymmetric encryption (Graphical representation) 5
Strengths and Weaknesses of Both 6
Strength of Symmetric Encryption 6
Strength of Asymmetric Encryption 6
Weakness of symmetric encryption 6
Weakness of Asymmetric Cryptography 6
Use of Symmetric and Asymmetric cryptography in IT sector 7
2. VPN and Cryptography in VPN 7
Types of VPN 8
Site–To–Site VPN 9
Remote Access VPN 9
3. Authentication of Users in Windows Environment 10
Integrated Windows Authentication 10
Basic Authentication 10
Digest Authentication 11
4. Kerberos Protocol 11
Kerberos V5 Protocol Standard 12
Encryptions used by the Kerberos v5 protocol 12
Helping Hands (web references) 13
1 Cryptography
Introduction
The concept of securing the messages through cryptography has a long history. The word cryptography stems
from the two Greek words "crypto" and "grafein" meaning "hidden" and "write" respectively. Julius Caesar is
credited with creating one of the earliest methods of cryptography system to send the message to his generals.
Cryptography simply means to encrypt your message into something else so that nobody can read it that is not
authorised to read the information. Only that person can

Use Of Visual Cryptography For Binary Images
An Introduction to Visual Cryptography for Binary Images
Okechukwu Ikoro
7061018
INSE 6110
Abstract
Visual Cryptography is a type of cryptographic scheme used to hide a secret image in shadow images called
shares or layers such that it can't be decrypted using the human visual system unless certain qualified subsets of
the shares are used. The secret image is encoded without the use of any cryptographic computations. The topic
of visual cryptography is a broad one with many fields however in this paper we will discuss the basic model of
visual cryptography and the extended model for binary images.
Keywords: Visual Cryptography. 1. Introduction
Secret sharing is a scheme that permits a secret message to be shared among a set P of n ... Show more content
on Helpwriting.net ...
The reason this scheme was considered remarkable was due to the fact that the secret message could be
decoded directly by the human visual system; hence it can be called the visual cryptography scheme. The
Decoding process involves printing the shares onto transparencies and superimposing them, the shares of a
qualified set will reveal the secret image without any cryptographic computation. In this paper we analyze the
basic model of visual cryptography for black and white images and the k out of n scheme. The basic scheme of
visual cryptography is called the (2, 2) model otherwise known as the 2 out of 2 model. This model involves
using 2 shares; a printed page of cipher text and a printed page of transparency (which serves as the secret key).
Both layers appear indistinguishable from random noise. The clear text is revealed by superimposing both
shares [2]. The basic model can be extended into the k out of n secret sharing problem which states; given a
written message, we can generate n transparencies (shares) such that the original message is visible if any k (or
more) are stacked together, but totally invisible if fewer than k transparencies are stacked together. A Visual
Cryptographic Scheme is mainly applied to a binary image, which contains a collection of black and white
pixels. Each pixel is handled separately and is encoded into p black and white sub pixels, which are printed in
close proximity to each other so that the human

A Closer Look At Cryptography Essay
A Closer Look At Cryptography
Ever since the earliest days of writing, people have had reasons to limit their information to a restricted group
of people. Because of this, these people have had to develop ideas of making their information unable to be
read by unwanted people. The general techniques used to hide the meaning of messages constitute the study
known as cryptography. "Ciphers, in general fall into three major classifications: 1. Concealment Cipher, 2.
Transposition Cipher, and 3. Substitution Cipher" (4). Cryptography protects information by altering its form,
making it unreadable to unwanted people or groups of people.
Cryptography, from the Greek kryptos, meaning hidden, and graphei, meaning to write. The origins of ... Show
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Advances in cryptography appeared with unprecedented frequency in the 1970's as strong encryption–based
protocols and new cryptographic applications emerged. On January 15th, 1977, the National Bureau of
Standards adopted an encryption algorithm as a federal standard, the Data Encryption Standard (DES), marking
a milestone in cryptographic research and development. In December 1980, the American National Standards
institute adopted the same algorithm for commercial use in the United States.
Cryptography has not been used solely for diplomacy and warfare. It has also played a major role in the
economy. The banking and finance industry has been the leader in promoting the use of cryptography for
protecting assets transferred via messages sent through large networks of computers and terminals. (2)
Francois Viete was born in 1540 in Fontenay–le–Comte in France, and died on December 13th, 1603 in Paris.
He was a French mathematician who introduced the first systematic algebraic notation and contributed to the
theory of equations. Although he was best known as a mathematician, he was also one of the best cipher experts
ever. By the end of the sixteenth century, the Spanish empire ruled over a large portion of the world

Advantages Of Quantum Cryptography
Quantum Cryptography
Introduction
Quantum cryptography is a new method for secret communications offering the ultimate security assurance of
the inviolability of a Law of Nature. Unlike traditional classical cryptography, which uses mathematical
techniques to restrict eavesdroppers, quantum cryptography is focused on the physics of information. The
development of quantum cryptography be classified as either "public–key" or "secret–key" methods. This
cryptography also involving two or more parties who may not trust one another. The best known cryptographic
problem is the transmission of secret messages. Suppose wish to communicate in secret. For example, you may
wish to give your credit card number to a merchant in exchange for goods, hopefully ... Show more content on
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Mathematical cryptography, as bad as it sometimes is, is the strongest link in most security chains. Our
symmetric and public–key algorithms are pretty good, even though they're not based on much rigorous
mathematical theory. The real problems are elsewhere: computer security, network security, user interface and
so on. "
Even quantum cryptography doesn't "solve" all of cryptography: The keys are exchanged with photons, but a
conventional mathematical algorithm takes over for the actual encryption.
Conclusion
Cryptography is used frequently. For example, credit card numbers are encrypted when you buy something on
the internet. Many government agencies are used cryptography to get messages safely around the world. Public
key cryptography is an innovation and which is an unavoidable part of almost all security protocol and
application. Being able to negotiate a shared secret between two devices online without the need of any
exchange of secret data created a breakthrough in secure network/internet

Steganography Analysis : Steganography And Cryptography
Chapter 1
INTRODUCTION
In this chapter we introduce why we have taken Steganography as our research area, we have also described the
properties of Steganography approach, types, applications of the research topic on which we work, short
overview of the study is given below.
1.1 Preface
The basic need of every growing area in today's world is communication. Everyone wants to keep the inside
information of work to be secret and safe. We use many insecure pathways in our daily life for transferring and
sharing information using internet or telephonically, but at a certain level it 's not safe. Steganography and
Cryptography are two methods which could be used to share information in a concealed manner. Cryptography
includes modification of a message in a way which could be in digesting or encrypted form guarded by an
encryption key which is known by sender and receiver only and without using encryption key the message
couldn't be accessed. But in cryptography it's always clear to intermediate person that the message is in
encrypted form, whereas in Steganography the secret message is made to hide in cover image so that it couldn't
be clearer to any intermediate person that whether there is any message hidden in the information being shared.
The cover image containing the secret message is then transferred to the recipient. The recipient is able to
extract the message with the help of retrieving process and secret key provided by the sender. A model of the
Steganography process

The Pros And Cons Of Cryptography
INTRODUCTION
Cryptography Is considered the most important thing by means of secure communication. It is used to encrypt
and decrypt data and provide secure communication between the sender and receiver. As a finance company,
the most important thing to look after is the process speed and security of the data. There are two types of
encryption and decryption methods known as a Symmetric key and Public key cryptography. Symmetric key
has set of algorithms such as Blowfish, two fish, DES, 3DES, AES etc and on the other hand Asymmetric key
has set of an algorithm such as Elliptic curve, Diffie–Hellman, DSA, RSA etc. These symmetric and
asymmetric keys have its own advantages and disadvantages. Hybrid cryptography is one of most famous
cryptography ... Show more content on Helpwriting.net ...
Asymmetric cryptography:
Asymmetric encryption is also known as public key encryption. This uses two keys for encryption and
decryption of data. The two keys are the Public key which it can be shared with anyone and the other one is a
Private key or secret key which should be kept secretly. Each user will have its own public key and private key.
Let's assume Alice and Bob are the sender and receiver. Alice(A) wants to send a message to Bob(B). Alice will
first encrypt(E) the plaintext(M) with Alice's public key and send to bob. Now Bob verifies Alice's message by
checking whether it is Alice's digital signature and then bob decrypts(D) the key using the bob private key. This
process will be the same if Bob sends Alice message.
↓ ↓
Plain text(M)→ → → →Plain text(M)
Advantages:
More secure when compared to symmetric key because the private key is not shared with each other.
Uses digital signature for encrypting data.

Cryptography Is Art Of Secret Writing
1.
The term cryptography develops from a Greek word which implies hidden or secret writing. Cryptography is art
of secret writing. The primary service provided by cryptography is capability to send information between two
participants in an effective way that halts others from reading it. This type of cryptography provides other
services namely,
integrity checking→ reassuring the recipient regarding a new message in which the message doesn 't seem to be
altered viewing that it was actually given by a legal source.
Authentication →verifying someone's (or something's) identity.
Messages within its original form is named plain text or clear text. The hidden info is generally known as cipher
text. The procedure for producing cipher text from plain text is named encryption. The reverse of encryption is
known as decryption. While cryptographers invent clever secret codes, crypt–analysts plan to break these codes.
Both these disciplines constantly make sure to keep in advance of one another. Ultimately, the successes of the
cryptographers rests on the cryptography systems are likely to involve both an algorithm as well as a secret
value. Here the secret value is called as key. The purpose for having a key alongside an algorithm is the idea
that it can be problematic to keep devising new algorithms which allows reversible scrambling of data, and it
will be hard to quickly explain a newly devised algorithm with the person you'd be willing to start
communicating securely.
2.

Visual Cryptography Essay
In order for the benchmarking scheme to be properly developed and executed, a developer needs to have an
awareness of the history of Visual Cryptography. The developer also needs an understanding of the underlying
concepts of Visual Cryptography and how they are used to generate shares of binary images. Recently, Visual
Cryptography has been extended to accommodate shares of gray and color images, further extending its
capabilities and versatility. This understanding of Visual Cryptography is necessary to allow an objective
comparison of all the different types of algorithms.
1.5. PROOF OF CONCEPT – BINARY IMAGES:
The process behind Visual Cryptography allows messages to be contained in seemingly random shares. The
generation of these ... Show more content on Helpwriting.net ...
2 Issue 6group occurring. A share generation scheme corresponding to k = 2 and n = 2. This is applied to a
binary image by assigning the corresponding sub–pixel grouping to the pixels throughout the image. This
results in two random shares where the message cannot be identified. The mathematical proof of this scheme
and its perfect encryption are shown in the original paper by Naor and Shamir Visual Cryptography".
1.6 EXTENSION TO GRAY AND COLOR IMAGES:
The process of Visual Cryptography, as developed through the original algorithm [12], was designed to be used
with binary images. This is illustrated from the nature of the shares and the encryption process documented
previously. If the secret messages being encoded contain text or binary images, the process shown in the
original algorithm works well. However, the world is not composed of solely black and white pixels. With the
increasing production of images in the digital age, gray and colour images have a pressing need for encryption
and protection as much, or more, as binary images.
1.6.1 GRAY IMAGES:
The development of an algorithm to encrypt binary images, they were also aware of the eventual need to
encrypt gray and colour images. In the last section of their paper, they proposed a technique which involved
printing each of the pixels in an image as half black – half white circles. This allowed the rotation angle of the
corresponding circles to vary

Cryptography Vs. Modern Cryptography Essay
Introduction
Cryptography is the practice and study of techniques for secure communication in the presence of third parties
called adversaries. More generally, cryptography is about constructing and analyzing protocols that prevent
third parties or the public from reading private messages; various aspects in information security such as data
confidentiality, data integrity, authentication, and non–repudiation are central to modern cryptography. Modern
cryptography exists at the intersection of the disciplines of mathematics, computer science, and electrical
engineering. Applications of cryptography include ATM cards, computer passwords, and electronic commerce.
Main Concept of Cryptography
Cryptography is the science of writing in secret code and is an ancient art; the first documented use of
cryptography in writing dates back to circa 1900 B.C. when an Egyptian scribe used non–standard hieroglyphs
in an inscription. Some experts argue that cryptography appeared spontaneously sometime after writing was
invented, with applications ranging from diplomatic missives to war–time battle plans. It is no surprise, then,
that new forms of cryptography came soon after the widespread development of computer communications. In
data and telecommunications, cryptography is necessary when communicating over any un–trusted medium,
which includes just about any network, particularly the Internet.
Within the context of any application–to–application communication, there are some specific

Cryptography and the Issue of Internet Security Essay...
High level encryption or cryptography is used in a number of applications ranging from those which impact
national security to those which are more mundane. Essentially, cryptography is the methodology of encoding
information so that one's privacy is ensured. This is particularly important when it comes to transactions which
occur over the Internet. The risk of individuals gaining access to personal information or information which is
critical to a country or a nation over the Internet is a very real one. The practice of cryptography lessens the
likelihood of this happening.
Part A –– Identification and Description of the Issue
A greater and greater percentage of the world population is gaining access to the Internet and incorporating ...
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We transmit and receive a massive amount of information through the Internet which by its very nature is
insecure and wild and free.
Some information we transmit and receive through the Internet is trivial, other is critical from either a personal,
business or national perspective. Without some form of encryption this information could not only fall into the
wrong hands but it could also be read and manipulated by those who intercepted it. This, according to the type
of information, could be disastrous from either a personal, business, or national perspective. It could be
presumed that intellectual property which currently belongs to its Creator would be freely disseminated around
the globe with no practical way to control who saw it or how they utilized it (anonymous,
http://www.cs.brown.edu/).
Part D–– Proposed Solutions
There are two possible solutions to the security of data on the Internet. These are TCP/IP and Cryptography.
TCP/IP sessions can be captured, however, by unauthorized personnel using devises such as IP packet sniffers
(Computer Reseller News PG). Cryptography, on the other hand, provides a single technology which has the
potential to address all of the above criteria to ensure safe Internet transactions.
The software provided by Hewlett Packard, VerSecure, offers an excellent and economical solution to the
problem of data security on the Internet (M2 Press

The Basic Model Of Visual Cryptography And The Extended Model
Abstract
Visual Cryptography is a type of cryptographic scheme used to encode a secret image into shadow images
called shares or layers such that it can't be decrypted using the human visual system unless certain qualified
subsets of the shares are used. The secret image is encoded without the use of any cryptographic computations.
In this paper we will discuss the basic model of visual cryptography and the extended model; using the k out of
n scheme.
Keywords: Visual Cryptography, Extended Visual Cryptography. 1. Introduction
Secret sharing is a scheme that permits a secret message to be shared among a set P of n participants. The secret
is shared in such a way that only qualified subsets of P can recover the secret, any nonqualified subset has no
information on the secret. We take into consideration, the problem of encrypting pictures and printed texts such
that it is perfectly secure without the hassle of using cryptographic computations. In 1979, Shamir [7] and
Blakley [8] introduced the concept of a threshold scheme. A (k, n) threshold scheme is a method whereby n
pieces of information of a secret key k, called shares are distributed among n participants so that the k cannot be
re constructed from the knowledge of fewer than k shares. In 1995 Naor and Shamir [1] proposed a new type of
cryptographic scheme, which could encode and decode secret images without any cryptographic computations.
The reason this scheme was considered remarkable was that the secret message

History of Cryptography
In the history of cryptography, the Enigma was a portable cipher machine used to encrypt and decrypt secret
messages. More precisely, Enigma was a family of related electro–mechanical rotor machines — comprising a
variety of different models. The Enigma was used commercially from the early 1920s on, and was also adopted
by the military and governmental services of a number of nations — most famously by Nazi Germany before
and during World War II. The German military model, the Wehrmacht Enigma, is the version most commonly
discussed. The machine has gained notoriety because Allied cryptologists were able to decrypt a large number
of messages that had been enciphered on the machine. The intelligence gained through this source — ... Show
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For example, the pin corresponding to the letter E might be wired to the contact for letter T on the opposite
face. The complexity comes from the use of several rotors in series — usually three or four — and the regular
movement of the rotors; this provides a much stronger type of encryption. When placed in the machine, a rotor
can be set to one of 26 positions. It can be turned by hand using a grooved finger–wheel which protrudes from
the internal cover when closed, as shown in Figure 2. So that the operator knows the position, each rotor has an
alphabet tyre (or letter ring) attached around the outside of the disk, with 26 letters or numbers; one of these can
be seen through a window, indicating the position of the rotor to the operator. In early Enigma models, the
alphabet ring is fixed; a complication introduced in later versions is the facility to adjust the alphabet ring
relative to the core wiring. The position of the ring is known as the Ringstellung ("ring setting"). The rotors
each contain a notch (sometimes multiple notches), used to control the stepping of the rotors. In the military
versions, the notches are located on the alphabet ring. The Army and Air Force Enigmas came equipped with
several rotors; when first issued there were only three. On 15 December 1938 this changed to five, from which
three were chosen for insertion in the machine. These were marked with Roman numerals to distinguish them:
I, II, III, IV and V, all with single notches

5 Ways to Measure the Quality of Your Cryptography Essay
5 Ways to Measure the Quality of Your Crypto Introduction Cryptography is definitely become a more
mainstream topic today. Almost every device in this world is connected to the internet and sharing information.
At the same time of the increasing of number in the device, the number of sensitive data in the information
shared between devices, application, and server is also increasing in a larger scale. That information must be
protected, so that the sensitive data will remain private. The dominance attack today is not just about Denial of
Services or Viruses just like 10 or 15 years ago. The nowadays attack is becoming more a specific purpose like
data theft, eavesdropping, getting access to sensitive data like credit card numbers, ... Show more content on
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Let's think about the private key in the asymmetric infrastructure, if a private root key is stolen, then the
trustworthy of the entire document issued by that root is undermined. And most of the time, it will need
reissuing of all digital credentials that is part of the infrastructure. So that will be a time consuming process, and
also at the same time, all the system that rely on those credentials is inoperable while the issuing process is
taking place. There is no better reason of a poor implementation quality than heartbleed vulnerability. The first
important thing here is that this is not a flaw on the SSL protocol itself, but it was a flaw in the OpenSSL
implementation of the protocol. Specifically it is a flaw in the heartbeat extension which keeps the session alive
between a client and server. So the door was widely open for attacker to crafts heartbeat request with short
"payload" that requests a mismatched sized amount of data (memory) in return. The memory can contain
sensitive data, passwords, keys, etc. Once the key has compromised, the attacker has the access to all of the
traffic. The attacker will still have the access until the software is patched, or the keys in SSL certificates are
updated. Many people already did the good thing in patching the OpenSSL, replacing SSL certificate, and
revoking the old certificate. But they made a critical mistake of reusing the same

Hybrid Cryptography Using Symmetric Key Encryption
Hybrid cryptography using symmetric key encryption
Sean laurel rex bashyam1, karthik Shankar2 ,Saitheja kadiyala3
Dept. of electrical engineering1,3
Dept. of computer science2
{skadiyal ,sbashyam ,kshankar}@my.bridgeport.edu professor Abdel–shakour Abuzneid
Dept. of computer engineering
University of bridgeport
Bridgeport , CT abuzneid@bridgeport.edu Abstract– Crucial methods are employed to deploy the majority
networks to acquire the data. Modern improvements stores, transfer data at higher rate. Traditional methods
which provide security to the information. Using single encryption algorithms are more prone to issues and
these are implemented without knowing its shortcomings. This proposed algorithms provides new step to avoid
shortcomings. We resemble some famous algorithms as follows. Firstly, we create a new algorithms, In order to
provide security issue and time constraint of operation. Secondly, We combine AES using multiplexing of keys,
Improvement of DES key size and blowfish algorithm, then we encrypt data using the proposed algorithm. This
can enhance the security and complicates the Encryption. In this paper we provide both the encryption and
decryption that supports in real time application and algorithm has a practical value.5
Index Terms– Hybrid encryption, Advance Encryption Standard(AES), Data Encryption Standard(DES),
Blowfish, Key length.
I. INTRODUCTION
Encryption is a method of converting plain text to cipher text using some base keys and

Cryptography : The Concept Of Public Key Cryptography
Abstract
As known today, Cryptography is the transformation of message under the control of secret key and keeping
information secure. The first major event in this history was the definition of the concept of public–key
cryptography. What we call public key cryptography was the major issue which was presented in 1976.[1]
According to the history of cryptography, Diffie Hellman and Merkle Have become famous as cryptographers
who explored the concept of public–key cryptography, while Rivest, Shamir and Adleman developing the new
kind of public key cryptography as RSA, the most beautiful implementation of this cryptosystem. Public key
cryptography was originally invented at the Government Communications Headquarters (GCHQ) in
Cheltenham which was the top secret establishment that was formed after World War. Public key distribution
became practical method for establishing a shared secret key over an authenticated communications channel
without using a prior shared secret.The keys for encryption and decryption in symmetric methods are the same
but in Public–key cryptography, also known as asymmetric cryptography, is a class of cryptographic algorithms
which requires two separate keys, one of which is private and one is public,because the key pair is
mathematically linked.
RSA is one of the first practicable public–key cryptosystems and is widely used for secure data transmission
It uses exponentiation modulo a product of two very large random primes, to encrypt and decrypt,

Cryptography And Embedded Systems Used
CRYPTOGRAPHY IN EMBEDDED SYSTEMS
Honey Pandey
Department of Electrical Engineering
State University of New York, University at Buffalo
Buffalo, New York 14260 honeypan@buffalo.edu Abstract–Embedded systems being designed are highly
reliable, respond well to the real time systems, provide flexible functionality and able to work given low power
sources. These various systems currently find their applications in the areas which involve managing very
extensive data including location determination, health, bank details and personal information which makes
security a vital factor of the embedded system domain. In this paper, the security algorithms involving
cryptography has been focused in the area of networks and basic processors. We study the two main
classification of cryptographic algorithms namely symmetric–key and public–key ciphers, used to protect
communication networks by utilizing the different security protocols as well as protecting data of the computer
systems. Symmetric–key ciphers and public key ciphers find their applications in fields governing data
encryption, authentication and digital signatures. Further becoming an essential part of the embedded systems
involving programmable network devices as there is a rise in the connectivity of the networks which increases
the role of cryptography algorithms from servers to sensors and smartcards. We study the implementation of
encryption algorithms on System on Chip dual core ARM model. However, majority of

Threats Of Cryptography And Steganography
The popularity of internet and its technologies increase day by day and so are the threats to the security of our
information transmitted through the internet. The unauthorized or illegal access of the data or tampering of data
is very high. In order to provide security of data being accessed by unauthorized people, information security is
required [1].
Cryptography and Steganography is too used to secure communication. According to dictionary.com:
Steganography is: "Hiding a secret message within a larger one in such a way that others cannot discern the
presence or contents of the hidden message" and Cryptography is "The process or skill of communicating in, or
deciphering secret writing or ciphers [2]."
The distinction between Cryptography and ... Show more content on Helpwriting.net ...
Once detected message is known Strong current algorithms are currently resistant to attack, larger expensive
computing power is required for cracking.
6. Steganography does not alter the structure of the secret message. Cryptography alters the structure of the
secret message.
1.2 History of Steganography
The first use of steganography is reported by Herodotus, the so–called father of history, who mentions that in
ancient Greek, hidden text was written on wax tablets. When Demeratus wanted to notify Sparta that the king of
Persia, Xerxes, intended to invade Greece, he wrote this message on a tablet and covered it with wax. To
recover the message the other people in Sparta simply had to scrape the wax off the tablet [3].
1.3 Steganography
The basic concept is that it has a cover object that is used to cover the original message image, a host object that
is the message or main image which is to be transmitted and the steganography algorithm to carry out the
required object. The output is an image called stego–image which has the message image inside it, hidden. This
stego image is then sent to the receiver where the receiver retrieves the message image by applying the de–
steganography

A Brief History of Cryptography
Computer science is a vast field that includes nearly everything relating to computers. Everyday there is
information transmitted all over the Internet. Pictures are uploaded, transactions are made on thousands of
online retail websites, and banking transactions take place everyday on the Internet. All of these transactions
have created a need for secure communications. People wish to keep things like banking, medical, and political
information from the eyes of unwelcome parties. This has created a need for cryptography. Cryptography is the
science or study of the techniques of secret writing, especially code and cipher systems, and is used by
everyone from the average citizen to the government and military.
Cryptography was first used ... Show more content on Helpwriting.net ...
Technology will continue advancing and that necessary to crack encryptions will become readily available to
those looking for it (12). Therefore, it is necessary to develop new methods to ensure security in the future. This
had led to quantum cryptography, which is a potentially uncrackable form of communication (12). According to
physicist Duncan Earl, quantum cryptography is a future–proof technology (13). Quantum cryptology requires
that the two parties create and share a secret key, unlike in public–key encryption (13). Instead of using
factoring to secure the key shared between two parties, photons of light are used (13). If a third party tries to
intercept the photons, discrepancies will show and the two parties will know the connection is no longer secure
(13). The law of physics states that in order to make a measurement on light, a disturbance must be made (13).
This means that it would be impossible to intercept the secret key without alerting the sender and receiver.
Public–key encryption relies on the trust that the computationally difficult problem used to share the key is too
strong for any computer out there to break (13). However, photons are not made for long distance use (13). In
order for this quantum cryptography theory to work for everyone, the range would need to be much larger.
Aside from the different types of crytopgraphy, there are also different functions (Goldwasser 16). Two
important types of

On the Development of Quantum Computers and Cryptography
On the Development of Quantum Computers and Cryptography
In 2010, the United States government, after accessing encrypted files by means of physical intervention,
exposed ten Russian sleeper agents; in 2013, the United States government, without any means of physical
intervention, surreptitiously collected and promptly decrypted many previously encrypted (Wood). Within this
decade, concerns regarding the dubious security of contemporary cryptography will begin to emerge as the
secrets of quantum computing quickly unravel. Companies that rely on Moore's law, which asserts that
computing power doubles every eighteen months, to justify using the theoretically weak cryptography scheme
known as RSA will succumb to the risks posed by ... Show more content on Helpwriting.net ...
These individuals cite a "three qubit impasse," which states that because quantum computers have not become
more complex than three qubits, they will not become more complex than three qubits. From the start of serious
research in 2001 up until recently, this argument had remained tenable. But, the human endeavor to create
technological advancements would not relent. This drive proved itself as successful in 2012, when D–Wave
Systems, a quantum computing company founded in 1999, announced that their work on a 512 qubit quantum
computer had concluded. D–Wave then went on to state that they would computer would reveal the computer
later that year, albeit with a limited range of abilities. Since then, companies such as Google and the National
Aeronautics and Space Association (NASA) have begun to work in conjunction with D–Wave to improve upon
their prototype and apply them to calculations to discover new potential. Nevertheless, dogmatic advocates for
RSA hold the proposition that their point still stands as these do not count as full–fledged quantum computers.
With the progression of time, the development of quantum computers will do as it has already done once and
relegate the power of the three qubit impasse to a continually smaller role.
While RSA performs its final show, a new system débuts. Praised by some as unbreakable, they call the method
"Quantum Key Distribution," (QKD) and in it lies

Cryptography Essay
Abstract–With the expansion in the field of computers and highly technically advanced communication
mediums like internet there is a necessity to secure the transmission of data. The information that is transmitted
over the internet is a highly sensitive and critical information which needs to be protected from adversaries,
hackers, and eavesdroppers etc. who bypass the existing security and perform dangerous actions. Cryptography
is the art and science of keeping the data transfer secure from adversaries, hackers and eavesdroppers.
Cryptography and its algorithm forms one of the essential components to the security mechanisms in order to
safeguard the data transmissions and data storage. Without the use of cryptography the emails and information
can be intercepted without any authorized access.
After researching academic papers related to cryptography I understand the basic working of DES algorithm
and the cracking of the DES algorithm by brute force technology. I would like to explore the cryptographic
algorithms, the flaws associated with the algorithm. In this paper, I will discuss about the DES algorithm and
deficiency with the DES algorithm. I will discuss the existing problem with double DES algorithm and the
basics about the Triple DES and the problem with respect to the Triple DES. A brief overview of AES has been
provided.
Introduction
Internet has reached a place where it has become an essential part of everyone's life, it has been one of the main
sources of

Taking a Look at Quantum Cryptography
Quantum Cryptography is the newest technology in the field of Encryption and proved to be most secure as of
now. In this paper we will discuss what quantum cryptography is and what makes it most secure and
unbreakable.
Introduction
All our classical computer cryptography methods are basically based on some mathematical calculations which
are quiet easy to implement in one direction but very difficult to process in the other direction. As RSA(Rivest–
Shamir–Adleman) algorithm which is one of the first practicable and most famous public–key cryptosystems,
RSA, is based on the technique of factoring large numbers which makes it secure. Difficulty in factoring
increases with number of digits in RSA key. For example, a 128 digit number would take millions of years to
factor with current computers.
There are still limitations in classical cryptography, it is purely mathematical and information cannot be
separated from its physical representation. In Classical physics, we use binary form to store and process the
data. In the 1980s, C.Bennet, P.Benioff, R.Feynman and others observed that new and very powerful ways of
information processing are possible with quantum mechanical systems. This gave birth to the concept of
quantum computing.
We have algorithms such as Shor's Algorithm, a quantum computer can break a very large number into its prime
factors otherwise which could take millions of years to be solved. The day when quantum cryptography will
become a reality, above

Cryptography : Applied Cryptography Rough Draft
Running Head: Cryptography 1 Cryptography 12
Applied Cryptography Rough Draft
ISSC 431
Professor Christopher Weppler
October 6, 2015
Introduction
Over the years, cryptography has been used to protect secrets, in a military capacity to make sure that either
hackers, enemies of the countries, do not intercept sensitive formation. Ciphers, and encryption blocks are
becoming so hard to break even the best super computers cannot break the codes in a timely fashion.
Encryption has been improved over the years, also has been around for thousands of years and this paper is
intended to explain about different forms of cryptography that either has been used or is still in use to this day.
This paper is about ... Show more content on Helpwriting.net ...
When coming to creating these types of security is predominately affiliated with the military, federal agencies,
governments and so forth. When talking about computer security cryptography this started back in the 60?s and
this came from a huge demand for the civilian sector to protect critical information and to transform data into a
digital form. Years later in the 70?s IBM took up the contract and started to create an encryption system for
communication systems, and that was known as DES (Digital Encryption Standard). Now with that being said
let 's discuss about identification/ entity authentication technique. There are differences between identification
and entity authentication, states about weak, strong and zero knowledge–based authentication. Entity
authentication procedure is in ?actual time? procedure in the sense that provides a guarantee that the parties that
are involved in carrying out some of the action of validation is functioning at the time of protocol execution.
When passwords come to entity authentication would be considered a weak authentication. When coming to
conventional password schemes that involve time natural outlines, which involved so–called weak
authentication general is between 6 to 10 characters and is a dictionary word. According to this passage ?
Conventional password schemes involve time–invariant passwords, which provide so–called weak
authentication. (Menezes & Oorschot & Vanstone, 1996) Now, when coming to

Developments in the Study of Cryptography Essay
Since the beginning of civilization, humans have needed a way to communicate in secret. Whether it be a letter
to a lover or a set of orders for an army, it would be paramount for these messages to arrive unknown and
untouched. However at some point, a person could easily apprehend the message; perhaps a spy or the letter
bearer, nevertheless the chance of the message being compromised would be quite high. Thus one would have
to change the message to appear as meaningless nonsense to those others than the intended recipient. This idea
formed the basis of cryptography, the backbone of digital security. Cryptography is the study and practice of
secure communications between two parties usually in the presence of a malicious entity, ... Show more content
on Helpwriting.net ...
Thus by only knowing what the cipher was, one would know what the original message was. Early ciphers were
primitive and involved the manipulation of the characters in a message. A transposition and substitution cipher
was very common in the classical age before computers. A transposition cipher involved merely arranging the
letters in a message while a substitution cipher involved changing the letters in a message to a different one in
the alphabet or to a symbol. Julius Ceasar used a form of substitution cipher in which he simply changed the
letter to its respected position three spaces in front of it in the alphabet. As one can imagine, such a cipher was
easy to break just from analyzing the ciphertext, and thus more complicated ciphers involving mathematical
theory were created. However as the advancement of cryptography continued, so did its contrary field of
cryptanalysis, the interpretation of protocols. This arrived at the discovery of frequency analysis; the process in
which the repetition of certain characters in a language is greater than those of other characters. Thus the
frequency of certain meaningless characters in a ciphertext would be higher than those of other ones. This
meant that a new method of encrypting messages had to be invented as any cipher could be broken. This new
method involved putting a private key ( a string of characters) into the cipher so that

Public Key Cryptography : Cryptography
PUBLIC KEY CRYPTOGRAPHY
Public key cryptography is also known as asymmetric cryptography. Public key cryptography is dependent
upon cryptographic algorithms which are based on mathematical problem. In Public key cryptography there are
two keys public key and private key. Public key is a mathematical code which is known to all i.e. it is widely
known. Private key is also a mathematical code but is known only to proprietor. There are many algorithm used
for public key cryptography some of them are discussed below.
 RSA algorithm. This algorithm is used in bank security and online banking. It is also used in secure
electronic communications. This algorithm is discussed briefly in the following section.
 DSA. Digital signature algorithm is a method in which digital signature of a person are saved and can be
used to authentication of electronic document. These types of authentication are used widely in modern world.
 Elliptic curve cryptography. It is based on algebraic stricter of a curve. In this type of cryptography key
required are smaller than other algorithm.
RSAALGORITHM This scheme was discovered by Ron Rivest, Adi Shamir and Len Adleman so it is called
RSA method. In this method we choose two large prime number p and q. These number should be very large an
acceptable range for this number is at least 256bit number. Bank use p and q of 512 bit. Now n = p*q then we
choose a number e such that the gcd of e and (p–1)(q–1) is, gcd(e,(p–1)(q–1)) = 1.This pair (n,e) form

Cryptography : Aes And Rsa
CRYPTOGRAPHY: AES and RSA
2 AES
The Advanced Encryption Standard (AES) was published by the National Institute of Standards and
Technology (NIST) in 2001. AES is a symmetric block cipher with variable key and fixed data length. The
structure of AES is quite complex and cannot be explained easily compared to RSA. In an AES, all operations
are performed on 8–bit bytes. The cipher takes a plaintext block size of 16 bytes (i.e. 128 bits). The key length
can be 16, 24, or 32 bytes. Depending on the key length, the algorithm is referred to as AES–128, AES–192 or
AES–256 respectively. The total number of rounds N also depends on the key size. The number of rounds is 10,
12 and 14 for 128–bit, 192–bit and 256–bit key length respectively. The ... Show more content on
Helpwriting.net ...
The output of the final round will be the cipher text.
2.1 DETAILED STRUCTURE OF AN AES ALGORITHM
The key expansion works as follows: The initial key is expanded into an array of words. Each word is four
bytes and for a 128–bit key, we will have 44 words (starting from w0 to w43). The initial key is copied into the
first four words of the expanded key. The remaining words of the expanded key are filled in four words at a
time. Each added word wi depends on the previous word wi–1 and the word four positions back wi–4. A simple
XOR is used and the key is therefore expanded into the remaining words.
The AES algorithm has 4 basic transformations:
2.1.1 SubBytes
In this step, the algorithm uses a look–up table (LUT) or a substitution table/s–box to perform a byte–by–byte
transformation on the state array. The byte s[i, j] becomes s'[i, j] after the substitution is done using the
substitution table. The inverse SubBytes uses the Inverse S–box to perform the transformation.
2.1.2 ShiftRows
This second step in each rounds is a permutation of rows by circular left shift. The inverse shift row
transformation is the inverse to ShiftRows as it performs the circular shift in the opposite direction.
2.1.3 MixColumns
The third step operates on each column separately. Each byte of a column is mapped into a new value which is
a function of all the four bytes in that column. It is designed as a matrix multiplication in which each byte is
treated as a polynomial in

Advantages And Disadvantages Of Visual Cryptography
Abstract– For preserving the security of data there has been tremendous research areas evolved and explored
since few years. Cryptography is seen to be the dominant strategy in the information security domain. To
differentiate security of multimedia data, visual cryptography is seen as the prominent way for data
confidentiality and secrecy of information being distributed.
The mechanism of visual cryptography is widely used approach which encrypts the secrete image into the many
meaningless share images and decodes by stacking some or all shares by human visual system. There are many
methods presented for visual cryptography with their own advantages and disadvantages.. Over the years , in
visual cryptography the scope of research mainly focused ... Show more content on Helpwriting.net ...
The pixel expansion problem occurred in extended VC scheme using general access structure was solved by
algorithm proposed by Lee and Chiu with addition of meaningful cover image in each share, without generating
noisy pixels. This approach consists of two phases. In the first phase, depending upon a given access structure,
meaningless shares are constructed with the help of an optimization technique. In the second phase, using
stamping algorithm the addition of cover images to each share is done. The construction problem of VCS for
general access structures is formulated as a mathematical optimization problem being solved using optimization
techniques. They have developed a hybrid method for EVCS constructions. With the use of stamping algorithm,
all present VC schemes can be changed so that the extended VC schemes are developed without redesigning
codebooks. The advantage of EVCS is the modularity. Each phase in the encryption procedure maintained
modularity thus its easy to modify each phase clearly. Another advantage is that as the density of the cover
images is adjustable, it is easy to modify the display quality of the cover images.

Essay about Claude Shannon's Contribution to Cryptography
Before approaching Claude Shannon's contribution to Cryptography, one must look at his prior work in
particular in the field of information theory, a field he theorized in his 1948 paper A Mathematical Theory of
Information. Shannon introduced a lot of the ideas that were mentioned and developed in this revolutionary
paper to the scientific community in his 1945 paper entitled A Mathematical Theory of Cryptography.
Indeed, during the Second World War, Shannon decided to join the Bell Labs, a research facility concentrating
many prominent scientists of the time who decided to use their talent to serve the war effort. While he was
working at the Bell Labs, the facility was in charge of many secret projects such as the development of the X ...
Show more content on Helpwriting.net ...
However, according to Shannon himself, what really launched him into the theorization of information was
Ralph Hartley's paper Transmission of Information. This paper developed "a measure of information that could
in principle be used for discrete or continuous signals." Hartley's publication also proved that a channel's
bandwidth defines how much information can be sent through it. Since a channel's bandwidth was limited and
since continuous signals could be broken down in small steps before being sent through the channel, Hartley
concluded that if the steps were small enough, the approximated signal would be not only close but identical to
the original signal. Finally, Hartley realized that information could be the "resolving of uncertainty." He
developed a mathematical formula according to this concept to quantify the amount of information in a message
but unfortunately, this formula was not complex enough and could not be applied to cases in which the
constituents of a message did not have all the same chances of being selected. Indeed, "in written English for
instance, some letters are used more frequently than others." Hartley's formula would not work when trying to
encode sentences for example because he couldn't model the fact that the letter E had more chances to be
selected than any other.
Nonetheless, Shannon realized the potential of these discoveries and went on

Parallel Computing Of Cryptography : A Literature Review
PARALLEL COMPUTING IN CRYPTOGRAPHY
A Literature Review
Presented to
Sharmin Khan
Department of Computer Science
San Jose State University
In Partial Fulfillment of the Requirements for the Class
CS 200W
By
Rachel Gonsalves
May 2016
Abstract
In today's world a lot of data is being exchanged via the internet. Sensitive data such as official documents,
bank details, credit card information, as well as personal information is being sent online. To maintain the
confidentiality, integrity and availability of this data, it needs to be encrypted. Cryptology deals with
cryptography and cryptanalysis, i.e., encryption and decryption of information. To keep the data safe from
intruders, various cryptographic algorithms are implemented. Parallel processing enhances the speed of these
systems and makes it more efficient. Parallel computation can be performed using multicore processors by
parallelizing the execution of algorithms in multiple cores. The main area of focus will be the parallelization of
Advanced Encryption Standard (AES) algorithm, which is widely in use today. The paper reviews the
implementation of AES algorithm on multiple cores and the speedups observed in the process.
TABLE OF CONTENTS
1. Introduction 4
2. Cryptography 5
3. Advanced Encryption Standard 5
4. Message Passing Interface 6
5. Parallel Processing System 8
6. Results and Performance 9 6.1. Encryption 9 6.2. Decryption 11
7. Conclusion 13 References 13

Cryptography : Key Encryption And Its Implementation Essay
INDEX PAGE NO.
1. ABSTRACT 1
2. INTRODUCTION 1
3. CRYPTOGRAPHY 1
4. ENCRYPTION AND DECRYPTION 2
5. CIPHER 2
6. HISTORICAL CRYPTOGRAPHY 3
7. WARDRIVEN CRYPTOGRAPHY (World War I) 7
8. WARDRIVEN CRYPTOGRAPHY (World War II) 9
9. MORDERN ENCRYPTION 11
10. SYMMENTRIC KEY ENCRYPTION AND ITS IMPLEMENTATION 12
11. ASYMMENTRIC KEY ENCRYPTION 14
12. RSA ENCRYPTION 15
13. STEGANODRAPHY 17
14. FUTURE MENTHODS OF ENCRYPTION 18
15. CONCLUSION 23
16. REFERENCES 24
ABSTRACT:
Primary purpose of cryptography is security. Cryptography has been present since thousands of years.
Encryption for a longer duration is a priority in many organizations. One among them is military, which used
cryptography to securely transmit a message. During 1980's there is great necessity of securely communicating
with others. Internet is present since 1960's and the World Wide Web came into existence during 1980's.
Throughout the world people access the internet. A World Wide Web, an electronic portal, is extensively used
by many people for communicating. People used World Wide Web to send electronic mails. This kind of
communication increased around the world. As the information passed between the two people may be hacked
by any other person, securing data and transmitting to the right person became important aspect. A deep
emphasis of encryption and cryptography will help all

A New Era Of Cryptography
A new era of Cryptography: Quantum Cryptography
Sandeepak Bhandari
Abstract:–
Security is the first priority in today digital world for secure communication between sender and receiver.
Various Cryptography techniques are developed time to time for secure communication. Quantum
Cryptography is one of the latest and advanced cryptography technique, it is different from all other
cryptography technique and more secure. It based on the Quantum of physics since its name which make it
more secure from all other cryptography and UN breakable. In this paper about quantum cryptography i.e
working, limitation and advantages discussed.
Keywords:–
Photon, Polarization filter, Advantage and Limitation of Quantum Cryptography.
Introduction: –
ID Quantique presents a quantum cryptography framework; will take after by the Magic innovations. These
frameworks use photons to send mystery encryption keys, concealing every key behind the most well known
tent of quantum mechanics, the Heisenberg vulnerability rule. This standard says, that it is difficult to know
both an article 's position and speed – in the meantime. Any email message, phone call or money related
encoded with these keys will be protected.
Quantum cryptography utilizes current learning of material science to build up a cryptosystem that is not ready
to be vanquished – that is, one that is totally secure against being traded off without information of the sender or
the beneficiary of the messages. "Quantum" alludes to the

Advantages And Disadvantages Of Cryptography
Cryptography is the science of retaining mathematics to encrypt and decrypt data. Cryptography enables you to
store sensitive data or dispatch it across insecure webs (like the Internet) so that it cannot be elucidate by
anybody except the aimed recipient. Cryptography is the science of safeguarding data; cryptanalysis is the
science of analyzing and obliterating safeguard communication. Classical cryptanalysis involves an interesting
combination of analytical reasoning, appeal of mathematical instruments, chart discovering, patience,
determination, and luck. Cryptanalysts are additionally yelled attackers. Cryptology embraces both
cryptography and cryptanalysis.
Cryptographic strength is measured in the era and resources it ought to demand to recoup the plaintext. The
consequence of forceful cryptography is cipher text that is tremendously tough to decipher lacking ownership
of the appropriate decoding tool. How difficult? Given all of today's computing manipulation and obtainable
time–even a billion computers replacing ... Show more content on Helpwriting.net ...
(There is nowadays facts that the British Hidden Service devised it a insufficient years beforehand Diffie and
Hellman, but retained it a martial secret–and did nothing alongside it.)
Public key cryptography is an asymmetric scheme that uses a pair of keys for encryption: a area key, that
encrypts data, and a corresponding confidential, or hidden key for decryption. You publish your area key to the
globe as keeping your confidential key secret. Anybody alongside a duplicate of your area key can next encrypt
data that merely you can read. It is computationally impossible to deduce the confidential key from the area
key. Anybody who has a area key can encrypt data but cannot decrypt it. Merely the person who has the
corresponding confidential key can decrypt the

Essay On Cryptography
5.1 Introduction: Two set of text images and one true sample image is taken for cryptography. In this proposed
work these three images are encrypted into various shares through MATLAB, so that after compiling specific
number of share the original image is visible. After encryption the performance analysis is done with the help of
PSNR and MSE values. 5.2 Main Input Images In the current work various set of text images are used for
crypto analysis. The sample image 1 and sample image 2 are the synthetically generated images for our own
study. The Reference image 1 and the Reference image 2 are the image taken from the work done by base
papers. And for the complex parametric evaluation a true colour image is also used for efficiency ... Show more
content on Helpwriting.net ...
In Figure 5.4(a) alphabet A from the original sample image is converted into cyan by subtracting green and blue
pixel from the original 256 pixel. (a) (b) (c) Figure 5.4: Image 1 CMY and Haftone Conversion (a) (b) (c)
Figure 5.5: Image 2 CMY and Haftone Conversion Similarly in figure 5.4(b) alphabet B is converted into
magenta by subtracting red and blue pixel from the original 256 pixel whereas yellow is observed in alphabet C
due to the subtraction of red and green pixels shown in figure 5.4(c) 5.5 RESULTANT SHARES & FUZZY
ANALYSIS In this section the shares are generated using the standard Floyd Steinberg half tone method [5] on
the image taken after merging the CMY components. Results of the Encryption of original sample image 1 are
resulted into four shares which is share 1, share 2, share 3 and share 4.shown in Figure 5.6. Share 1 Share 2
Share 3 Share 4 Figure 5.6: Shares for different input sample images 1 Share 1 Share 2 Share 3 Share 4 Figure

History of Cryptography
History of Cryptography AN EASY TO UNDERSTAND HISTORY OF CRYPTOGRAPHY Contents 1.
Introduction 2. Classical Encryptions (Ancient Times) 3. Classical Encryptions (Middle Ages) The Cipher of
Mary Queen of Scots Vigenère Ciphers Uesugi Cipher 3 4 6 6 6 7 4. Modern Ciphers: Ciphers during World
War I and the Emergence of Encryption Machines German Communication Cables Disconnected by the United
Kingdom Zimmermann Telegram ADFGVX Cipher The Birth of Enigma 8 8 8 8 9 5. Modern Ciphers:
Encryptions in the Computer and Internet Era DES Cipher Public–Key Cryptosystem RSA Cipher Decrypting
the DES Cipher Responsive Action of Cipher Enhancements for SSL 10 10 10 11 12 12 6. The Future of
Encryption 7. Conclusion: ... Show more content on Helpwriting.net ...
The Caesar cipher method of encryption involves replacing each of the letters of the alphabet in the original text
by a letter located a set number of places further down the sequence of the letters in the alphabet of the
language. The sender and receiver agree in advance to replace each letter of the alphabet in the text by a letter
that is, for example, three letters further down in their alphabet. An encryption method that involves rearranging
the sequence of characters according to a specific rule such as that shown above is referred to as a "substitution
cipher". Substitution ciphers are a well–known encryption method, and they are the most commonly used
encryption method in the history of encryption. The modern encryption machine called "Enigma" described
below made it possible to apply the substitution cipher method with a higher level of sophistication. Plain text
characters (text that has not been encrypted) Encryption characters SMKRATNGQJUDZLPVYOCWIBXFEH
ABCDEFGHIJKLMNOPQRSTUVWXYZ example of a 26–letter alphabet: 26 x 25 x 24 x .... = 400,000,0
00,000,000,000,000,000,000 patterns!) and making decryption dramatically more difficult. example of
encryption. Hieroglyphics were long considered impossible to ever read, but the discovery and study of the
Rosetta

Cryptography And The Egyptian Tomb Of A Nobleman
Since written history and most likely prior, the world has been trying to hide and keep others away from things
considered important enough. Civilization has a desire to hide this information from others. This could be for
reasons of espionage, having a secret that shouldn't be shared or some other well–guarded right. Cryptography,
encryption and various other methods have been used in history and are constantly evolving into what we are
using today to protect our data from getting stolen, hacked and lives peeked at.
Cryptography, at least in some form, has been around since 1900 BC where the first known evidence had been
seen in an Egyptian tomb of a nobleman, Khnuhotep II. Here, there are unusual hieroglyphic symbols that the
scribe used in the place of more ordinary ones that one would expect. It is thought that the purpose of changing
these symbols, it was not to hide the message, but make it seem like it was more dignified. However, evidence
of cryptography has been traced back to the most of the major early civilizations. Arthasharta, an ancient Indian
treatise, helps tell of an espionage service and mentions secret writing that their spies had used on
assignements. Julias Caesar also had his very own cipher. It was a form of encryption to relay secret messages
to his generals that were on the war front. It is a substitution cipher, and the most widely mentioned in history. A
substitution cipher is where a plain text message would have each character

Cryptography : Using Encryption Decryption Technique
Cryptography is the technique of providing secured communication in the presence of third parties. It is mostly
use between individuals, military forces As we know there are various aspects which are important in
information security such as confidentiality, data integrity, authentication and one important thing is that there
should be assurance form the third party to contract and they should not deny of the authentication of their
signature on any document so, all these are the vital part of the cryptography.
It is the method of protecting information by encrypting it into unreadable format. And then we can share
decoding technique that can be used for decoding technique to the requested use who wants to see the original
information, so we can prevent this information from unwanted users to see it. But the problem is, the
techniques which we are used getting more complex.
Encryption–Decryption technique: Recent cryptography uses mathematical algorithms to design it. This
algorithms should design as strong as possible so that it cannot break by any other third party system. The
techniques which can be used to do cryptography are microdots, merging words with images and by different
symbols. One more way to achieve cryptography by ordinary text into cipher text called as encryption and
getting back original information known as decryption. This technique mostly used by cryptographer to achieve
cryptography.
As I have explained above cryptography mostly focuses on following

Cryptography, Cryptography And Decryption Keys Essay

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