Vigenere Cipher: Trends, Review and Possible Modifications (original) (raw)
Related papers
Survey: Recent Modifications in Vigenere Cipher
IOSR Journal of Computer Engineering, 2014
In order to secure the information there are different polyalphabetic substitution ciphers are available. Out of these Vigenere cipher is considered to be most efficient and simplest one. Due to its repeating nature of the key it is also vulnerable to attacks. To overcome this, there are many researches going on to modify the conventional Vigenere Cipher. In this paper we have presented a review of recent modifications in Vigenere cipher and its cryptanalysis.
An Enhanced Vigenere Cipher For Data Security
In today's world the amount of data that is exchanged has increased in the last few years so securing the information has become a crucial task. Cryptography is an art of converting plain text message into unreadable message. Encryption algorithms play an important role in information security systems. Encryption is considered as one of the most powerful tool for secure transmission of data over the communication network. Vigenere technique is an example of polyalphabetic stream cipher; it has various limitations such as Kasiski and Friedman attack to find the length of encryption key. In this paper an enhanced version of traditional vigenere cipher has been proposed that eliminates the chances of Kaisiski and Friedman attack. Proposed technique also provides better security against cryptanalysis and pattern prediction.
An Extended Hybridization of Vigenere and Caesar Cipher Techniques for Secure Communication
Procedia Computer Science, 2016
Cryptography is one of the most popular fields of study these days as it is necessary to maintain the confidentiality of the data which is sent over the network. There are various cipher techniques available for encrypting the messages such as vernam cipher, mono-alphabetic cipher, poly-alphabetic cipher, etc. One of the most popular cipher techniques is the vigenere cipher. It is a poly-alphabetic cipher technique which uses the vigenere table for the process of encryption of alphabets. This paper extends the vigenere table by including numerical data, so that the numbers can also be encrypted using this technique. It combines the encryption process of vigenere and Caesar cipher for getting the cipher text from the given plaintext and key.
A Modified Version of Vigenere Cipher using 95×95 Table
International Journal of Engineering and Advanced Technology, 2020
Cryptography is a current field of research at the moment as it can be crucial to offer protection to extremely delicate and confidential records from criminal wrongdoings throughout transmission over the network. The vigenere cipher is one of the standard cryptographic algorithms that prevent attackers from understanding the raw data throughout the transmission. The traditional vigenere cipher encrypts only the alphabetic plaintext with a 26×26 vigenere table because it includes only 26 English alphabets A to Z. The researcher extended the original vigenere table into 95×95 which introduces all possible characters, mathematical symbols, digits, and punctuations that are available on an ordinary QWERTY keyboard layout that can be encrypted easily by this technique and conjointly introduced case sensitivity. The objective of this modification makes the cryptanalysis procedure more difficult and increases the information security.
Modified Vigenère cipher algorithm based on new key generation method
Indonesian Journal of Electrical Engineering and Computer Science, 2022
Nowadays, as communication and network technologies evolve in modern life, ensuring the confidentiality of a cryptography system has become a critical requirement. The Vigenère cipher is attracting the attention of cryptography specialists, although the Vigenère cipher algorithm has a problem. The problem is due to a repeating encryption key. As a result of the multiple cryptographic approaches described in the literature, this paper proposes a novel encryption strategy for safe and secure data exchange by utilizing a new key generation process. The proposed encryption approach avoids the issue of repeating keys. Additionally, the classic Vigenère cipher encrypts the plaintext using a 26x26 Vigenère table, the researcher modified the original Vigenère table to 95x95, which adds more potential letters, mathematical symbols, numerals, and punctuation to a standard QWERTY keyboard layout. Additionally, the researcher added case sensitivity. To observe the performance of the proposed method, the index of coincidence and entropy have been calculated. The obtained results confirm the high performance of the proposed algorithm in comparison to the other algorithms used in this paper. The primary goal of this paper is to make cryptanalysis extremely complex and to promote data security.
International Journal of Computer Applications, 2021
Vigenère cipher is an ancient elementary method that uses a series of Caesar shifting for encrypting plaintext to ciphertext protecting it from adversaries. However, a frequency analysis attack is vulnerable in this type of cipher technique. This paper aims to enhance the security of the Vigenère cipher in a hybrid cryptosystem using a randomized approach including pseudorandom substitution, rearranging, padding, etc. In this approach, a complex key generation algorithm is used that generates a pair of subkeys from an input key. One of the subkeys, Subkey1 is used to generate an intermediate ciphertext. The other key, Subkey2 is used to further scramble the ciphertext. The slightest change in the input symmetric key produces an entirely different key pair. Hence, different encrypted results. It also increases the ranges of characters that Vigenère cipher can encrypt by including all ASCII and extended ASCII. Finally, the symmetric key is encrypted with the public key of RSA solving the key distribution problem of the symmetric cipher. This enhanced and modified Vigenère cipher in the hybrid cryptosystem overcomes all limitations of classical cipher and acts as a bridge between classical and modern cryptography.
Modified Vegenere Cipher to Enhance Data Security Using Monoalphabetic Cipher
International Journal of Artificial Intelligence & Robotics (IJAIR), 2019
The rapid progression of exchange data by public networks is important, especially in information security. We need to keep our information safe from attackers or intruders. Furthermore, information security becomes needed for us. Many kind cipher methods of cryptography are improved to secure information such as monoalphabetic cipher and polyalphabetic cipher. Cryptography makes readable messages becoming non-readable messages. One of the popular algorithms of a polyalphabetic cipher is Vigenere cipher. Vigenere cipher has been used for a long time, but this algorithm has weaknesses. The calculation of the encryption process is only involving additive cipher, it makes this algorithm vulnerability to attacker based on frequency analysis of the letter. The proposed method of this research is making Vigenere cipher more complex by combining monoalphabetic cipher and Vigenere cipher. One of the monoalphabetic ciphers is Affine cipher. Affine cipher has two steps in the encryption proce...
2021 7th International Conference on Computer and Communications (ICCC)
In recent years, many modifications have been done to combat the weaknesses of the Vigenè re Cipher Algorithm. Several studies have been carried out to rectify the flaw of the algorithm's repeating key nature by increasing the key length equal to that of the plain text. However, some characters cannot be encrypted due to the limited set of characters in the key. This paper modified the algorithm's key generation process using a Pseudo-Random Number Generator to improve the algorithm's security and expanded the table of characters to up to 190 characters. The results show that based on Monobit examination and frequency analysis, the repeating nature of the key is nonexistent, and the generated key can be used to encrypt a larger set of characters. The ciphertext has a low IC value of 0.030, which is similar to a random string and polyalphabetic cipher with an IC value of 0.038 but not equal to a monoalphabetic cipher with an IC value of 0.065. Results show that the modified version of the algorithm performs better than some of the recent studies conducted on it
Implementation of Vigenere Cipher as Cryptographic Algorithm in Securing Text Data Transmission
Innovare Academics Sciences Pvt. Ltd, 2020
Data theft is the process of stealing digital information from victims who do not know it in order to jeopardize privacy or o btain confidential information. Data theft becomes a problem for individual computer users, as well as large companies. Every individual has not covered the possibility of information theft because of someone's negligence. In safeguarding data, we need a technique that can help someone in keeping the data a secret. Data theft is unavoidable, but data security can be improved to preve nt data misuse. Vigenere algorithm, which is a cryptographic technique, can help secure data from data misuse. This algorithm works by shifti ng each character in the plaintext for the key provided. The key used can be a series of characters or are words that are difficult to guess by people who want to commit a crime. Implementing the Vigenere Cipher algorithm will guarantee data security.
The Effect Of Varying Key Length On A Vigenère Cipher
Vigenère cipher is one of the polyalphabetic substitution ciphers. Its weakness is the key repetition. To overcome this weakness there are many researchesgoing on to modify the key generation. In this paper a key generator function isimplemented with C++. Itgenerates a key with length depends on the message security level.This level is determined by the sender of the message, according to the security importance of the message. The security level determines the key length, which is a ratio from the plain-text message. This ratio varies from 10% to 100% from the plain-text length. This paper studies the effect of varying the key length on the performance of Vigenère cipher andits frequency analysis attack. When the key length increases the encryption and decryption time increases, the frequency analysis attack becomes more difficult and also the confusion is increased.