Efficient Modular Exponentiation Methods for RSA

Güner, Hatice
Cenk, Murat
Çalık, Çağdaş
RSA is a commonly used asymmetric key cryptosystem that is used in encrypting and signing messages. The efficiency of the implementation is an important factor in effectively using the system. The RSA algorithm heavily depends on the modular exponentiation operation on large integers. A drawback of this system is that it becomes inefficient so quickly when the parameters are adjusted to increase security. This situation causes the operations to be performed with large numbers. Therefore, implementations require the utilization of faster methods than the traditional ones. One popular modular exponentiation method is the repeated squaring and multiplication algorithm. In this study, we examine some of the modular exponentiation algorithms and implement them for comparison with the repeated squaring and multiplication algorithm. The results suggest that particular cases of studied methods provide at least 23% improvement over the repeated squaring and multiplication algorithm.
ISC Turkey 2015, (30 - 31 Ekim 2015)


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Citation Formats
H. Güner, M. Cenk, and Ç. Çalık, “Efficient Modular Exponentiation Methods for RSA,” presented at the ISC Turkey 2015, (30 - 31 Ekim 2015), 2015, Accessed: 00, 2021. [Online]. Available: https://hdl.handle.net/11511/75120.