Dynamic feedback based modified SNOW 2.0

SNOW family is static in nature and it is based on static feedback. It is used to encrypt data from user input form to a binary form for secure communication. All the existing versions of snow family are affected by guess and determine attacks. Modified version of SNOW 2.0 shows more resistance against guess and determine attacks, but there are still some limitations. This paper has proposed a new version of stream cipher modified SNOW 2.0 based on dynamic feedback. The proposed technique uses dynamic feedback based shift register to overcome the limitations of previous techniques and it increases security of communication channel. Dynamic feedback is determined by using dynamic number generator function. It generates dynamic tap position to increase the security of modified version. Dynamic feedback makes difficult for attacker to guess the exact values. Finally, the analysis and experimental results show that the proposed technique has more resistance against Guess and Determine (GD) attacks as compared to static feedback based modified SNOW 2.0.

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