Date of Submission


Date of Award


Institute Name (Publisher)

Indian Statistical Institute

Document Type

Doctoral Thesis

Degree Name

Doctor of Philosophy

Subject Name



Theoretical Statistics and Mathematics Unit (TSMU-Kolkata)


Barua, Rana (TSMU-Kolkata; ISI)

Abstract (Summary of the Work)

This thesis describes research that I conducted during the course of my Ph.D. study at Indian Statistical Institute (ISI), Kolkata. I hope that this work is of use and will be carried on.I would like to begin by thanking my supervisor, Prof. Rana Barua for his support and endless patience. He has provided me background in Cryptography, Combinatorics and Theory of Automata during the period 2000-2002 of my course work of M.Tech in Computer Science at Indian Statistical Institute. I really appreciate his extraordinary patience in reading my numerous inferior drafts, for listening and analyzing all my ideas, forcing me to be thorough with details, not to take shortcuts and for all his interesting discussions and contributions. He is a co-author of all my works included in this thesis. His constant supervision, valuable advice and continuous encouragement have added greatly to the quality of this thesis.I most sincerely thank Prof. Bimal Roy for introducing me into the area of Cryptography and Coding Theory with such an excellence during my course work of M.Tech. I was fascinated by his teaching since the first day. Apart from being grateful for introducing me to cryptography, I also have to thank him for providing all supports through advise, encouragement and financial aid.Another person of importance to my work is Dr. Palash Sarkar. I would like to express my utmost gratitude to him for introducing me to the field of Elliptic Curve Cryptography and Pairings. I have enjoyed and benefited from his fruitful discussions and unlimited valuable suggestions. He gave me insight to find problems with several revisions of papers and helped me to learn to think. He inspired me to design key agreement protocols in multi-party scenario and contributed significantly on some works described in this thesis and my research. In fact, Chapter 3 and Chapter 5 are based on our published papers which are done jointly with him. The most important for me was probably that he taught me how to write. If I am a better writer or speaker because of my time as a Ph.D. student, it is largely because of him and Prof. Rana Barua.I must thank all anonymous referees of my published papers, whose comments have always added a new dimension to my works. I am thankful to the faculty and staff of the Stat Math Unit and Applied Statistics Unit for all the help during my studies in ISI. I would also like to express my special thanks to all members of Cryptology Research Group of ISI.Moreover I thank many other people who have provided much emotional supports in my life. In particular, I wish to express my whole hearted gratitude to my family and friends for their continuous support and encouragement. I dedicate this thesis to them.


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Creative Commons Attribution 4.0 International License
This work is licensed under a Creative Commons Attribution 4.0 International License.


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