Secure password generation through statistical randomness tests

Uslu, Aycan
Both symmetric and asymmetric cryptographic algorithms must firstly be robust against brute force. The key needs to be choosen uniformly and randomly from the key space. It is possible to assure randomness by using statistical randomness tests which are also critical for other cryptographic issues as well. There is still an issue to be elaborated: the most well-known tool for attacking againts passwords namely dictionary attacks. These attacks are based on trying all keys from a particular subspace of the key space, which are composed of words from daily life and their variations. In this study we focus on the randomness of the keys but we are not interested with latter issue that is dictionary attacks. The one who use our tests to generate key must check it regarding specified dictionaries. 


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Modular exponentiation has an important role in many cryptographic algorithms. These exponentiation methods differ in the bases used and their representations, the repeating aspect, and for which algorithms they are used for: fixed or variable base. Our research aims to compare the efficiencies and implementation timings for some selected algorithms. Also, we look at the options for using a dedicated cubing algorithm, and compare them with the current algorithms.
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Akcengiz, Ziya; Doğanaksoy, Ali; Department of Cryptography (2014)
Randomness is one of the most important parts of the cryptography because key generation and key itself depend on random values. In literature, there exist statistical randomness tests and test suites to evaluate randomness of the cryptographic algorithm. Although there exist randomness tests, there is no mathematical evidence to prove that a sequence or a number is random. Therefore, it is vital to choose tests in the test suites due to independency and coverage of the tests used in the suites. Sensitivity...
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Şeker, Okan; Doğanaksoy, Ali; Department of Cryptography (2014)
Random values are considered as an indispensable part of cryptography, since they are necessary for almost all cryptographic protocols. Most importantly, key generation is done by random values and key itself should behave like a random value. Randomness is tested by statistical tests and hence, security evaluation of a cryptographic algorithm deeply depends on statistical randomness tests. In this thesis we focus on randomness postulates of Solomon W. Golomb in particular, second postulate which is about r...
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Güner, Hatice Kübra; Cenk, Murat; Department of Cryptography (2015)
Modular exponentiation is an essential operation for many asymmetric key cryptosystems such as RSA in which encryption and decryption are based on modular exponentiation. Therefore, efficiency of the system is effected with running time of the modular exponentiation algorithm. At the same time, key sizes also influence the efficiency of the algorithm. Over the years key sizes had to be increased to provide security. To make RSA practical, one of usable choices is acceleration of the modular exponentiation a...
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Cenk, Murat; Negre, Christophe (2014-09-01)
Some applications like cryptography involve a large number of multiplications of binary polynomial. In this paper we consider two, three and four-way methods for parallel implementation of binary polynomial multiplication. We propose optimized three and four-way split formulas which reduce the space and time complexity of the best known methods. Moreover, we present a block recombination method which provides some further reduction in the space complexity of the considered two, three and four-way split mult...
Citation Formats
A. Uslu, “Secure password generation through statistical randomness tests,” M.S. - Master of Science, Middle East Technical University, 2017.