The Experts below are selected from a list of 2394 Experts worldwide ranked by ideXlab platform
Dipanwita Roychowdhury - One of the best experts on this subject based on the ideXlab platform.
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strengthening nls against Crossword Puzzle attack
Australasian Conference on Information Security and Privacy, 2007Co-Authors: Debojyoti Bhattacharya, Debdeep Mukhopadhyay, Dhiman Saha, Dipanwita RoychowdhuryAbstract:NLS is a stream cipher proposal submitted to eSTREAM project. In SAC 2006 Cho and Pieprzyk presented a linear distinguishing attack called Crossword Puzzle attack on NLS where they have shown that the bias of the distinguisher is around O(2-30). In this work we have proposed a new function modular Slash which is nonlinear in nature and strongly resistant against Linear Cryptanalysis. Replacing the modular addition in the nonlinear filter (NLF) of NLS we have shown that the Crossword Puzzle attack presented by Cho and Pieprzyk can be prevented. In the modified NLS the bias of the linear distinguisher reduces to around O(2-60). Also we have shown that the implementation cost of modular Slash, in terms of hardware and time delay, is less than modular addition. The proposed function could be an interesting alternative to modular addition, due to its better cryptographic properties and lesser implementation cost.
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ACISP - Strengthening NLS against Crossword Puzzle attack
Information Security and Privacy, 1Co-Authors: Debojyoti Bhattacharya, Debdeep Mukhopadhyay, Dhiman Saha, Dipanwita RoychowdhuryAbstract:NLS is a stream cipher proposal submitted to eSTREAM project. In SAC 2006 Cho and Pieprzyk presented a linear distinguishing attack called Crossword Puzzle attack on NLS where they have shown that the bias of the distinguisher is around O(2-30). In this work we have proposed a new function modular Slash which is nonlinear in nature and strongly resistant against Linear Cryptanalysis. Replacing the modular addition in the nonlinear filter (NLF) of NLS we have shown that the Crossword Puzzle attack presented by Cho and Pieprzyk can be prevented. In the modified NLS the bias of the linear distinguisher reduces to around O(2-60). Also we have shown that the implementation cost of modular Slash, in terms of hardware and time delay, is less than modular addition. The proposed function could be an interesting alternative to modular addition, due to its better cryptographic properties and lesser implementation cost.
Rushikesh K. Joshi - One of the best experts on this subject based on the ideXlab platform.
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Automation Strategies for Unconstrained Crossword Puzzle Generation.
arXiv: Artificial Intelligence, 2020Co-Authors: Charu Agarwal, Rushikesh K. JoshiAbstract:An unconstrained Crossword Puzzle is a generalization of the constrained Crossword problem. In this problem, only the word vocabulary, and optionally the grid dimensions are known. Hence, it not only requires the algorithm to determine the word locations, but it also needs to come up with the grid geometry. This paper discusses algorithmic strategies for automatic Crossword Puzzle generation in such an unconstrained setting. The strategies proposed cover the tasks of selection of words from a given vocabulary, selection of grid sizes, grid resizing and adjustments, metrics for word fitting, back-tracking techniques, and also clue generation. The strategies have been formulated based on a study of the effect of word sequence permutation order on grid fitting. An end-to-end algorithm that combines these strategies is presented, and its performance is analyzed. The techniques have been found to be successful in quickly producing well-packed Puzzles of even large sizes. Finally, a few example Puzzles generated by our algorithm are also provided.
Debojyoti Bhattacharya - One of the best experts on this subject based on the ideXlab platform.
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strengthening nls against Crossword Puzzle attack
Australasian Conference on Information Security and Privacy, 2007Co-Authors: Debojyoti Bhattacharya, Debdeep Mukhopadhyay, Dhiman Saha, Dipanwita RoychowdhuryAbstract:NLS is a stream cipher proposal submitted to eSTREAM project. In SAC 2006 Cho and Pieprzyk presented a linear distinguishing attack called Crossword Puzzle attack on NLS where they have shown that the bias of the distinguisher is around O(2-30). In this work we have proposed a new function modular Slash which is nonlinear in nature and strongly resistant against Linear Cryptanalysis. Replacing the modular addition in the nonlinear filter (NLF) of NLS we have shown that the Crossword Puzzle attack presented by Cho and Pieprzyk can be prevented. In the modified NLS the bias of the linear distinguisher reduces to around O(2-60). Also we have shown that the implementation cost of modular Slash, in terms of hardware and time delay, is less than modular addition. The proposed function could be an interesting alternative to modular addition, due to its better cryptographic properties and lesser implementation cost.
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ACISP - Strengthening NLS against Crossword Puzzle attack
Information Security and Privacy, 1Co-Authors: Debojyoti Bhattacharya, Debdeep Mukhopadhyay, Dhiman Saha, Dipanwita RoychowdhuryAbstract:NLS is a stream cipher proposal submitted to eSTREAM project. In SAC 2006 Cho and Pieprzyk presented a linear distinguishing attack called Crossword Puzzle attack on NLS where they have shown that the bias of the distinguisher is around O(2-30). In this work we have proposed a new function modular Slash which is nonlinear in nature and strongly resistant against Linear Cryptanalysis. Replacing the modular addition in the nonlinear filter (NLF) of NLS we have shown that the Crossword Puzzle attack presented by Cho and Pieprzyk can be prevented. In the modified NLS the bias of the linear distinguisher reduces to around O(2-60). Also we have shown that the implementation cost of modular Slash, in terms of hardware and time delay, is less than modular addition. The proposed function could be an interesting alternative to modular addition, due to its better cryptographic properties and lesser implementation cost.
Charu Agarwal - One of the best experts on this subject based on the ideXlab platform.
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Automation Strategies for Unconstrained Crossword Puzzle Generation.
arXiv: Artificial Intelligence, 2020Co-Authors: Charu Agarwal, Rushikesh K. JoshiAbstract:An unconstrained Crossword Puzzle is a generalization of the constrained Crossword problem. In this problem, only the word vocabulary, and optionally the grid dimensions are known. Hence, it not only requires the algorithm to determine the word locations, but it also needs to come up with the grid geometry. This paper discusses algorithmic strategies for automatic Crossword Puzzle generation in such an unconstrained setting. The strategies proposed cover the tasks of selection of words from a given vocabulary, selection of grid sizes, grid resizing and adjustments, metrics for word fitting, back-tracking techniques, and also clue generation. The strategies have been formulated based on a study of the effect of word sequence permutation order on grid fitting. An end-to-end algorithm that combines these strategies is presented, and its performance is analyzed. The techniques have been found to be successful in quickly producing well-packed Puzzles of even large sizes. Finally, a few example Puzzles generated by our algorithm are also provided.
Dhiman Saha - One of the best experts on this subject based on the ideXlab platform.
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strengthening nls against Crossword Puzzle attack
Australasian Conference on Information Security and Privacy, 2007Co-Authors: Debojyoti Bhattacharya, Debdeep Mukhopadhyay, Dhiman Saha, Dipanwita RoychowdhuryAbstract:NLS is a stream cipher proposal submitted to eSTREAM project. In SAC 2006 Cho and Pieprzyk presented a linear distinguishing attack called Crossword Puzzle attack on NLS where they have shown that the bias of the distinguisher is around O(2-30). In this work we have proposed a new function modular Slash which is nonlinear in nature and strongly resistant against Linear Cryptanalysis. Replacing the modular addition in the nonlinear filter (NLF) of NLS we have shown that the Crossword Puzzle attack presented by Cho and Pieprzyk can be prevented. In the modified NLS the bias of the linear distinguisher reduces to around O(2-60). Also we have shown that the implementation cost of modular Slash, in terms of hardware and time delay, is less than modular addition. The proposed function could be an interesting alternative to modular addition, due to its better cryptographic properties and lesser implementation cost.
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ACISP - Strengthening NLS against Crossword Puzzle attack
Information Security and Privacy, 1Co-Authors: Debojyoti Bhattacharya, Debdeep Mukhopadhyay, Dhiman Saha, Dipanwita RoychowdhuryAbstract:NLS is a stream cipher proposal submitted to eSTREAM project. In SAC 2006 Cho and Pieprzyk presented a linear distinguishing attack called Crossword Puzzle attack on NLS where they have shown that the bias of the distinguisher is around O(2-30). In this work we have proposed a new function modular Slash which is nonlinear in nature and strongly resistant against Linear Cryptanalysis. Replacing the modular addition in the nonlinear filter (NLF) of NLS we have shown that the Crossword Puzzle attack presented by Cho and Pieprzyk can be prevented. In the modified NLS the bias of the linear distinguisher reduces to around O(2-60). Also we have shown that the implementation cost of modular Slash, in terms of hardware and time delay, is less than modular addition. The proposed function could be an interesting alternative to modular addition, due to its better cryptographic properties and lesser implementation cost.