Cryptography: Basic Concepts and Its Importance in Network and Web Security

This paper introduces the basic concepts of cryptography, its importance in network and web security, and the different types of cryptography algorithms. It also discusses network security, web security, and network attacks. Subject: Cryptography, Course Code: NA, Course Name: NA, College/University: NA

Running head: CRYPTOGRAPHY
Cryptography
Name of the Student
Name of the University
Author Note

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Table of Contents
Introduction....................................................................................................................2
Cryptography..................................................................................................................2
Network Security.......................................................................................................3
Web Security..............................................................................................................5
Network Attacks.........................................................................................................6
Conclusion......................................................................................................................8
References......................................................................................................................9

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Introduction
Cryptography is the branch of cryptology, and it is in the field of implementing the
cryptographic system. Cryptology has another branch called as the cryptanalysis where the
cryptographic systems were breaks (Stallings, 2017). Cryptography is the area where
mathematics and computer science were concentrates on the criteria to secure communication
between two parties while the third party is the present while this approaches, concepts such
as encryption, decryption, signing, generating of the pseudo-random numbers, and others.
There are four principles of the cryptography and these are confidentiality, data
integrity, non-repudiation, and authentication. Confidentiality means there are a set of rules
which should be maintained and that limits the access or adds restrictions on some of the
information. The data integrity means which have to check the consistency and the accuracy
of the data in its full life-cycle (Lindell & Katz, 2014). The authentication is the term which
confirms an attribute is true or not of a datum which was said to be true by some entity. And
non-repudiation works on the inability of an author of a statement to ensure it and some
information to deny it.
This paper introduces the basic concepts of the cryptography. The paper includes
what cryptography is, what are the different forms of the cryptography that are used in the
modern generation and how it is helpful for the people (Bennett & Brassard, 2014). Further
how the implementation of the cryptographic process can help in integrating data security.
What major changes are needed in the recent future are also a major part of the report.
Cryptography
In Cryptography at first it works on in encrypted data which is referred to as plain text
and then the plaintext is encrypted into ciphertext which will be again decrypted to using
plain text (Kosba et al., 2016). The concept of encryption and decryption is fully based on the

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type of the cryptography scheme. Cryptography is heavily used to encrypt and decrypt data
with the creation of mathematical algorithms. And the cryptanalysis has the concept of only
analyzing and breaking the encryption schemes. There are three types of cryptography
algorithms. And the algorithms will be further categorized in the basis of a number of keys
for encryption and decryption (Mirhosseini et al., 2015). The secret key cryptography which
is commonly known as SKC and also called symmetric encryption because it uses a single
key to work on both encryption and decryption. Basically used for privacy and
confidentiality. The public key cryptography also known as PKC and also called as
asymmetric scheme because it uses the different key for the encryption and the decryption
and this is used for the purpose of authentication, non-repudiation and key exchange. And the
last hash function uses mathematically transformation to encrypt data irreversibly by the
digital fingerprint. And it is used in message integrity.
Network Security
The cryptography is the component of network security and it is concerned about the
destruction, unauthorized use of network resources and how to protect from this. Network
security works on all kind of data it can access and plays a vital role in the wireless network
systems. Security is a lack of knowledge and everyone are not aware of these things and
people need to know these things (Cimato & Yang, 2017). Encryption is another component
of network security and is the most efficient way to decrease data loss. In the network, safety
encryption will apply the crypto facilities at the network transmission layer on the top of the
data link layer and below the application layer. Encryption in a network security has another
name as network layer encryption. The term encryption, in the network security system,
works through internet protocol security layers and helps in the process of standardizing the
internet engineering task force. This also helps in the process of construction of the structure
for private communication over an internet protocol network. Internet protocol executes the

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architecture and then show to be the same as encrypted packets to unencrypted packets and
can rout easily by the internet protocol network.
There are several companies which work on network encryption merchandise and
facilities such as Oracle, Cisco, and others (Peikert, 2016). The knowledge of encryption has
become the important and essential part of network security. It is very important to protect
data. The two type of keys are used to protect data and network and these are a public key
and private key. Public key was designed in the year 1976 and referred to cipher architecture
type. It is basically used to encrypt data and corresponding private key to decrypt that data.
The public key is based upon very secure and it does not require any undisclosed public key
among sender and receiver. It purposefully uses to store private emails and keep on mail
servers for many times. The private key is also secured key and also called an encryption key
or decryption key to send and receive messages from senders and receivers so that every
message can be encrypted and decrypted. Nowadays PIN is the most important and secured
way to login into any system and the network.
Every individual user must have an individual login and password to access the
network and it will help in increasing the security level. Some important things to ensure
secure password in the network system are as follows, extended password, change password
anytime, avoid utilization of similar password, the necessity to change the password regularly
(Van Tilborg & Jajodia, 2014). Every user has to keep a long type password as a short
password is very easy to analyze. Users should change the password regularly so that can
easily get that. Users should not use the same password over and over because it can naïve
administration to think. Users always should check their work accounts from a remote
location and should frequently change the password. Symmetric encryption system works
like a private key because it is also used to encrypt and decrypt data and exchanged between
two keys. There are two types of the symmetric encryption system, stream ciphers, and block

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ciphers. Stream ciphers are the bit of information and can works on 1 bit at a time. For that, it
can work faster to generate and have an important security gap as it is smaller. There are
some types of attacks which can implement the data to reveal. The block ciphers encrypt the
data by breaking them into blocks and encrypts the information in each of the blocks and the
information has a fixed size that can be of 64 bits and commonly use in triple DES and AES
(Pirandola et al., 2015. The symmetric encryption algorithm is basically used in internet
protocol sector. For wireless network RC4 is commonly used. These symmetric encryption
algorithms are very fast and they can easily generate in hardware because of their relatively
low complexity. For weak password, the symmetric encryption system can break. The
asymmetric encryption system is a setup of a key pair and these two keys are of use for
encryption and another one for decryption. One key can encrypt the data and another one can
decrypt the data. One key is for the public so that anyone can access it and another key is for
private use only so that only the receiver can access it. Asymmetric encryption algorithm has
some elements, plaintext, encryption algorithm, public and private keys, ciphers text and
decryption algorithm (Chen et al., 2015. Plain text is a text message which usesn the
algorithm. To conduct the mathematical operations the encryption algorithm is used. RSA is
very slow but it can establish a secured channel over a non-secure channel such as the
internet.
Web Security
Web security is very important in daily life in terms of online searching, emails, and
others. Web services have many problems like spam, viruses, and others. Some of the risks
that are present in web security such as internet protocol address identifying the computer and
some attacks are there such as SQL injection attacks (Abadi & Andersen, 2016). Tools of
web security are spike proxy, power fuzzer, sec point penetrator, net sparked, OWASP, Gama
sec, Nikto scanner, perimeter check. There are untrained users who set up unauthorized

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networks and workstation. Lack of monitoring is there in every organization and these have
some loopholes in monitoring but there are some detection tools which can be used to secure
the system. For weak encryption, the wireless LAN may be harmful and the weak encryption
says that users cannot enable it for insufficient encryption standards. In wireless for
connecting to the network or listening to the network easily, the airwaves are used. And then
the result is that the data is encrypted with strong encryption (Androulaki et al., 2017). When
hackers try to decrypt the messages then they use WEP encryption. The hackers can easily
enter through circumventing firewalls in wireless LAN and allow other to come. Therefore
the private information lost for unsecured holes in the network.
Network Attacks
There are some cryptographic attacks which are implemented to damage the security
of cryptographic algorithms. These attacks are a part of cryptanalysis which is useful for
deciphering the encrypted data. There are six methods of cryptographic attacks basically
three of them are based on plain text methods and the rest of the three are based on cipher
text-based methods(Xu et al., 2015. A recognized plaintext attack can be explained as an
attack wherever the cryptanalyst creates a connection between the plaintext and the ciphertext
by accessing them. The ciphers text uses the process of ciphers such as the frequency
analysis, Caesar cipher can help in breaking the ciphers and the ciphers txt can only attack
where a cryptanalyst has the access to the cipher's text but does not have the access to the
plaintext (He & Zeadally, 2015). This type of attacks is commonly used against asymmetric
cryptography where the public key can be accessed by the cryptanalyst(Xu et al., 2015. The
chosen ciphertext attack is an attack where the ciphertext is chosen by the cryptanalyst and
able to find the perfect matching plain text. And this attack can be done by a decryption
oracle (Arnon-Friedman et al., 2018). In adaptively chosen plaintext attacks and adaptively
chosen ciphertext attacks based on the prior result, the next plain text and cipher text is

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chosen by the cryptanalyst. Side channel attacks are another information which is commonly
used for physical implementation of a cryptographic algorithm. The cryptanalyst has the
access to the plaintext and the ciphertext and also to the cryptographic algorithm that has
been mentioned in the cryptographic attack. There are many side channels operators. The
open SSL is one the example of the side channels. In open SSL there are two types of
multiplication are done and those are done for equal sized words and normal multiplication
for unequal sized words (Pandey & Verma, 2015). A network using SSL TCP/IP connection
is done to detect the difference in the speed. Brute force attacks are the attacks which
generally attempts every possible key. The brute force attack is an attack which occurs in a
known plaintext or known ciphertext only. Meet in the middle attacks is generally used
against the cryptographic algorithm and the algorithms which uses multiple keys for
encryption.
The attack versus the duple DES is the best instance of men in the middle attack.
Double DES is better than the 56 bit DES because its strength is high. It is a known plaintext
attack and the meet in the middle attack generally do their work in the plain text and the
subsequent ciphertext. Different cryptanalysis and the linear cryptanalysis are similar attacks
and these are commonly used in the iterative symmetric key block cipher. The iterative cipher
works by collecting multiple rounds of encryption. In these two attacks, the cryptanalyst is
the way to changing the ciphertext between the round of encryption (Xu et al., 2015). The
main of the strong encryption is to create ciphertext which is shown randomly where a small
text change plain text can result in a random change in the resulting ciphertext. Linear
cryptanalysis is based upon the plain text attack and for this, they have to access a large
number of pairs of plain text and cipher text which are encrypted pairs which are unknown
key. It only observes the statistical analysis on the large amounts of ciphertext in the one
round of decryption. Differential cryptanalysis is commonly known as the chosen plaintext

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attack that is used to generate bonding in the ciphertexts which are occurred by two related
plaintexts. It is based on two inputs and two outputs of a cryptographic algorithm. By using
the XOR operation which is a Boolean exclusive to a plain text the plain text pair is created.
By using all related subkeys the cryptanalyst encrypts its XOR pair and the plain text. The
subkeys which become the random candidate key has the least random pattern. The birthday
attack is mainly used in the destruction of hashing algorithms (Bos et al., 2014). It is basically
based on the birthday paradox that based on the statement that if there are some numbers of
people in a room then the chances one are slightly greater than fifty present that two of them
will share their birthdays. The main motive of this is to remember the odds of any two
persons sharing their birthdays and it will be the odds of sharing the birthday with the
particular people (Krawczyk et al., 2014). This attack is mostly seen in MS5 or SHA1 to
attempt destructions in the hash function.
Conclusion
Thus concluding the topic it can be said that cryptography is one of the most
important concepts of the network and web security. In the recent future, the concept of the
cryptography can complex than before. This paper has elaborate on the cryptography that
how it works. There are several paths to attack every one of these systems. Nowadays two
different schemes are used, and one of them is symmetric schemes and the second one is
asymmetric schemes. In symmetric schemes, two parties have to get the same key to encrypt
the communication. And these have to be exchanged the key initially. And the concept of
asymmetric schemes both the parties have the public and private keys. One having the public
key can use it to encrypt a message for another one and the other having the private key
which is to be used for decrypt the message. Hence it can be said that the concept of the
cryptography must be used in a proper manner so that there is less number of any security
faults. One of the major thing that has to be noted that with the increase of the technology the

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fraudsters are also trying to advance and hence proper care has to be taken care in order to
reduce network and web related attacks.

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