Yazar "Ozer, A. Bedri" seçeneğine göre listele

Listeleniyor 1 - 4 / 4
  • Küçük Resim Yok
    Öğe
    Hybrid pseudo-random number generator for cryptographic systems
    (Springer, 2015) Avaroglu, Erdinc; Koyuncu, Ismail; Ozer, A. Bedri; Turk, Mustafa
    For a powerful cryptographic system, high-quality random number streams are essential. Those raw pseudo-random number generators (PRNG) that are used to generate high-quality random numbers have some disadvantages, such as failure to meet the R4 security requirement. Therefore, use of random number sequences generated by these generators in a cryptographic system puts the entire system at risk. This study proposes a new hybrid PRNG by means of an additional input introduced to transition and output functions used in a raw PRNG system in order to eliminate this risk. The additional inputs to the designed system have been implemented via the true random number generator developed by using the Sprott 94 G chaotic system on FPGA. The random number streams obtained from the recommended hybrid structure have been subjected to the NIST 800.22 and FIPS statistical test, which have given good results. According to these results, it has been proved that the recommended hybrid PRNG system meets the R4 security requirement and can be used in cryptographic applications.
  • Küçük Resim Yok
    Öğe
    Implementation of Non-periodic Sampling True Random Number Generator on FPGA
    (Soc Microelectronics, Electron Components Materials-Midem, 2014) Tuncer, Taner; Avaroglu, Erdinc; Turk, Mustafa; Ozer, A. Bedri
    Random numbers are essentially required for various cryptographic applications. It is ideal to use nondeterministic random number generators in cryptography field since they are able to generate high-quality random numbers. In this paper, a Ring Oscillator (RO) based True Random Number Generator (TRNG) that can be used in cryptographic applications was developed. In this system, random numbers are generated by non-periodic sampling. Sinusoidal iterator with chaotic behavior was used for generation of non-periodic sampling signals. In TRNG system; three different scenarios, each of which contains three inverters, with 25, 10 and 5 RO circuits were implemented on FPGA environment. Randomness tests of numbers that are generated by TRNG with non-periodic sampling were carried on according to the NIST 800.22 test suit. The results have shown that the proposed system can be used in the cryptographic systems.
  • Küçük Resim Yok
    Öğe
    A New Method for Hybrid Pseudo Random Number Generator
    (Soc Microelectronics, Electron Components Materials-Midem, 2014) Avaroglu, Erdinc; Tuncer, Taner; Ozer, A. Bedri; Turk, Mustafa
    Powerful cryptographic systems need qualified random numbers. Qualified random numbers need providing good statistical qualities, not predicting and not re-generating. The numbers generated by raw Pseudo Random Number Generators (PRNG) can be predicted when their seed value are detected or the functions used in the system are not complicated enough. Moreover, the stream generated repeats itself after its period is exhausted. Due to these shortcomings mentioned above, raw PRNGs are not suitable for the cryptographic applications. In order to eliminate these shortcomings, by adding an additional input to the raw PRNG system, a hybrid structure is suggested in this study. In the hybrid system, a chaotic attraction in order to generate pseudo random number and a TRNG system having 5 Ring Oscillator (RO) each of which includes 3 inverters as the additional input were used. The random numbers obtained from the suggested hybrid structure were exposed to the NIST 800.22 statistical tests and it is shown that hybrid system can be used in the cryptographic systems.
  • Küçük Resim Yok
    Öğe
    A novel chaos-based post-processing for TRNG
    (Springer, 2015) Avaroglu, Erdinc; Tuncer, Taner; Ozer, A. Bedri; Ergen, Burhan; Turk, Mustafa
    The usage of numbers generated by true random number generators is critical in cryptology field due to security reasons. On the other hand, generated raw numbers rarely have good statistical properties because entropy sources used in true random number generators can be influenced by environmental factors. Post-processing is required for TRNGs to overcome the shortcomings of generated raw numbers. In this paper, a chaos-based post-processing technique is proposed as an alternative to other post-processing techniques in the literature. Logistic map is used in post-processing to ensure that numbers generated by RO-based TRNG are high quality. Four different scenarios considering RO-based TRNG structure are examined in order to observe the effects of the logistic map. The proposed system is set on EP4CE115F29C7-based Altera FPGA board, and the statistical properties of generated numbers are tested according to NIST 800.22 test suit and TESTU01. The degree of non-periodicity of the developed system was inspected by employing scale index method. The generated series pursuant to the obtained results was non-periodic. The results suggest that logistic map can be used as post-processing.