The International Arab Journal of Information Technology (IAJIT)


Improvement in Rebalanced CRT RSA Seema Verma and Deepak Garg

Many improvements have been made since the RSA orig in in terms of encryption/decryption speed and memory saving. This paper concentrates on the performance improvement. Rebalanced RSA is designed to improve the decryption speed at the cost of encryption speed. Further work was done to improve its encryption speed in terms of rebalanced Chinese Remainder Theorem (CRT) variants. Rebalanced CRT va riants improved the encryption speed at the cost of decryption speed. This paper also improves the performance of the enc ryption side in rebalanced RSA, while still maintaining the same decryption speed as in rebalanced RSA by adding the multiprime RSA feature to the rebalanced CRT variant. Proposed scheme gains the same advantage in encryption side as in rebalanced CRT variants, besides it is 2 times faster at decryption side than rebalanced CRT variants. Due to the use o f multiprime feature, the key generation time is also decreased in this case. It is decreased approximately by a factor of 2.39 f rom rebalanced RSA CRT variant. Comparison of the R SA variants with the new scheme is shown in tabular and graphical way fo r better analysis.

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