**Quantum Key Distribution and Its Cryptanalysis.**

An academic program on Quantum Optics and Quantum Technology (June 5-8, 2017) at Indian Association for the Cultivation of Science (IACS), organized by its Department of Materials Science and Raman Centre for Atomic and Molecular Sciences, Kolkata, India, June 6, 2017.**Classical and Quantum Computation: Friends or Foes?**

Academic Discussion on Classical and Quantum Computation and Information, organized by J C Bose Science Heritage Museum (JCBSHM) in collaboration with Cambridge University Press (CUP), Kolkata, India, May 18, 2017.**From Classical Computation to Quantum Information.**

Workshop on Quantum Technologies, Jagadish Chandra Bose Centre for Advanced Technology (JCBCAT), Defence Research & Development Organisation (DRDO), Kolkata, India, April 18, 2017.**Quantum Cryptography.**

National Instructional Workshop on Cryptology (March 10-12, 2017), Department of Computer Science and Systems Engineering, Andhra University, Visakhapatnam, India, March 12, 2017.**Quantum Computers: Myth vs. Reality.**

Second North-East Workshop on Computing: Theory and Applications at Tezpur Centre of Indian Statistical Institute (Feb 20-24, 2017), organized by Computer and Communication Sciences Division (CCSD) of the Institute, February 24, 2017.**Secure Communication in Pre-Quantum, Quantum and Post-Quantum Era.**

International Conference on Advanced Computing (ICAC, Oct 26-27, 2016), Maulana Abul Kalam Azad University of Technology, Kolkata, India, Oct 27, 2016.**Introduction to Quantum Cryptography.**

National Instructional Workshop on Cryptology (April 6-8, 2016), Central University of Rajasthan, Ajmer, India, April 8, 2016.**The death and rebirth of classical cryptography in a quantum world.**

International School and Conference on Quantum Information (Feb 9-18, 2016), Institute of Physics (IOP), Bhubaneswar, India, February 10, 2016.**Pre-Quantum Cryptology.**

International School and Conference on Quantum Information (Feb 9-18, 2016), Institute of Physics (IOP), Bhubaneswar, India, February 9, 2016.**Pre-Quantum Information Theory.**

International School and Conference on Quantum Information (Feb 9-18, 2016), Institute of Physics (IOP), Bhubaneswar, India, February 9, 2016.**An Overview of Quantum Information and Computation.**

Lecture Meeting organzied by Computer Chapter of IEEE Kolkata Section, Jadavpur University, Kolkata, India, January 29, 2016.

Click HERE to view / listen.**Quantum Rational Secret Sharing.**

Seminar at Physics and Applied Mathematics Unit (PAMU), Indian Statistical Institute, Kolkata, India, August 19, 2015.**Interplay between Mutual Information and Success Probability: A Deeper Look into the Security of BB84.**

Seminar at Theoretical Physics Division, Physical Research Laboratory (PRL), Ahmedabad, India, November 21, 2014.**An Introduction to Quantum Key Distribution.**

Cryptography Seminar Series, Indian Statistical Institute (ISI), Kolkata, India, May 21, 2014.**Is classical information and computation dead in a quantum world?**

Seminar at the Department of Computer Science & Technology, Indian Institute of Engineering Science and Technology (IIEST), Shibpur , Howrah, India, April 17, 2014.**No Cloning Theorem and Quantum Key Distribution.**

Seminar at the Department of Mathematics, Birla Institute of Technology and Science (BITS) Pilani, K. K. Birla Goa campus, Goa, India, December 6, 2013.*Classical Cryptography in a Quantum World.*

Satellite Meeting on Quantum Correlation and Its Possible Application in Communication and Cryptography (Sep 2-3, 2013), Indian Statistical Institute (ISI), Kolkata, India, September 2, 2013.*Architectural and Implementation Issues of Robust Cryptosystems in the Quantum Era: A Case Study.*

Network Meeting of the Alexander von Humboldt Foundation (November 28-30, 2012), Institute of Theoretical Informatics, Karlsruher Institut fur Technologie (KIT), Karlsruhe, Germany, November 29, 2012.**Pseudo-Random Generators: from Classical to Quantum Security.**

Seminar at the Ultra High-Speed Mobile Information and Communication (UMIC) Research Centre, Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, Germany, July 11, 2012.*Protecting Privacy: from Stone-age to Quantum World.*

Seminar for the Faculty Members of the Department of Computer Science & Engineering, the Department of Information Technology and the Department of Master of Camputer Application, Siliguri Institute of Technology, Siliguri, India, January 20, 2012.*Four-State BB84 is as Secure as the Six-State Protocol.*

Security Fundamentals (SF) Meeting, Research Center for Information Security (RCIS), National Institute of Advanced Industrial Science and Technology (AIST), Tsukuba, Japan, November 15, 2011.

##### Invited Talks on Quantum Information and Computation

##### Invited Talks on Classical Cryptology

**Cryptography: a saga of reincarnation!**

Annual Technical Fest – DAKSHH, Heritage Institute of Technology, Kolkata, India, March 20, 2017.**Random number generation and its applications.**

Workshop on Mathematics, Computer Science and Cryptology (Jan 30-31, 2017), Bhawanipur Education Society College, Kolkata, India, January 30, 2017.**From Battle-fields to Bank ATMs — the Evolution of Cryptology.**

Seminar at Bhawanipur Education Society College, Kolkata, India, September 16, 2016.**How Randomness Is Used in Cryptography.**

One-day State-Level Workshop on Mathematics, Computer Science and Cryptology, Department of Mathematics, Computer Science and Science Forum, Mrinalini Datta Mahavidyapith, Birati, Kolkata, India, August 23, 2016.**From Randomness to WiFi Security and Beyond.**

Seminar at Department of Mathematics and Statistics, Himachal Pradesh University, Shimla, India, June 6, 2016.**Some Ores from Crypto-mines.**

Special Research Talk for Summer Internship in Cryptology (May 16 – July 15, 2016), Indian Statistical Institute (ISI), Kolkata, India, May 20, 2016.**Introduction to Stream Cipher Security.**

Workshop on Cryptology for North Eastern States (January 21-27, 2016), Applied Statistics Unit (ASU), Indian Statistical Institute (ISI), Kolkata, India, January 27, 2016.**Introduction to Stream Cipher Design.**

Workshop on Cryptology for North Eastern States (January 21-27, 2016), Applied Statistics Unit (ASU), Indian Statistical Institute (ISI), Kolkata, India, January 25, 2016.**Overview of Hardware Cryptography.**

Workshop on Digital Design (Nov 6-8, 2015), Advanced Computing and Microelectronics Unit (ACMU), Indian Statistical Institute (ISI), Kolkata, India, November 6, 2015.**Non-randomness of Reduced-round Salsa20 and Its Implications.**

Workshop on Security of Symmetric Ciphers in Network Protocols (May 25-29, 2015), International Centre for Mathematical Sciences (ICMS), Edinburgh, under EPSRC-DST Indo-UK Initiative in Applied Mathematics, May 28, 2015.**Differential Cryptanalysis of Salsa20.**

Targeted Training Program at Indian Statistical Institute (ISI), Delhi, India, March 20, 2015.**Linear Cryptanalysis of HC-128.**

Targeted Training Program at Indian Statistical Institute (ISI), Delhi, India, March 20, 2015.*An Application of Random Graphs in Cryptanalysis.*

ASU Seminar Series, Applied Statistics Unit (ASU), Indian Statistical Institute (ISI), Kolkata, India, March 3, 2015.*A Short Tour of Symmetric Key Encryption: Stream Ciphers.*

National Level North East Workshop on Cryptology (January 22-24, 2015), C.I. College, Bishnupur, Manipur, India, January 23, 2015.*A Short Tour of Symmetric Key Encryption: Block Ciphers.*

National Level North East Workshop on Cryptology (January 22-24, 2015), C.I. College, Bishnupur, Manipur, India, January 23, 2015.*Statistical Cryptanalysis of RC4 as used in WEP, WPA and TLS: Foundations and Important Results.*

Winter School on Interplay Between Statistics and Cryptology (December 1-5, 2014), organized by Applied Statistics Unit, Indian Statistical Institute, Kolkata, in collaboration with EPSRC-DST Indo-UK Initiative in Applied Mathematics, December 3, 2014.*Number Theoretic Algorithms for Public Key Cryptography.*

Course on Cryptography, Department of Computer Science & Engineering, Tripura Institute of Technology (TIT), Agartala, India, November 8, 2014.**From Insecure Randomness to Secure Pseudo-randomness: A journey with permutation over integers modulo N.**

Colloquium at Department of Computer Science, University at Albany, State University of New York, U.S.A., July 21, 2014.*Permutation, Randomness and WiFi Security.*

Seminar at Department of Computer Science, University of Nevada, Las Vegas, U.S.A.,July 17, 2014*Symmetric Key Cryptography: Stream Ciphers.*

Short Term Course on Cryptography (May 18-24, 2014), Department of Mathematics, Indian Institute Technology (IIT) Kharagpur, India, May 18, 2014.**Introduction to Classical Cryptography.**

Short Term Course on Cryptography (May 18-24, 2014), Department of Mathematics, Indian Institute Technology (IIT) Kharagpur, India, May 18, 2014.*Introduction to Block Ciphers.*

Staff Development Programme on Cryptography & Information Security (Sep 21-25, 2013), Govt. College of Engineering & Textile Technology – Berhampore, Murshidabad, India, Sep 22, 2013.*Introduction to Cryptology.*

Staff Development Programme on Cryptography & Information Security (Sep 21-25, 2013), Govt. College of Engineering & Textile Technology – Berhampore, Murshidabad, India, Sep 21, 2013.*Biases and Distinguishers of the RC4 Stream Cipher.*

Seminar at Crypto and Security group, Department of Electrical and Information Technology, Lund University, Sweden, March 27, 2013.*A Look into (Non-)Randomness of RC4 Stream Cipher.*

Theory Seminar at Center for the Theory of Interactive Computation (CTIC),Aarhus University, Denmark, March 22, 2013.*The RC4 Landscape: Hills, Canyons and Plateaus.*

Seminar at Security and Cryptography Laboratory (LASEC), School of Computer and Communication Sciences (I&C), Ecole Polytechnique Federale de Lausanne (EPFL), Switzerland, February 8, 2013.*Connection between Information Theory and Security.*

Seminar at the Institute for Communication Technologies and Embedded Systems (ICE), Rheinisch-Westfälische Technische Hochschule (RWTH) Aachen, Germany, June 26, 2012.*An Overview of Classical Information and Classical Cryptography.*

Workshop on Information and Security in Quantum World (March 28-30, 2012), Indian Statistical Institute, Kolkata, India, March 28, 2012.*Distinguishing Attacks on Stream Ciphers.*

ASU Seminar Series, Applied Statistics Unit (ASU), Indian Statistical Institute (ISI), Kolkata, India, November 29, 2011.*Trivial and Non-trivial Issues of TRIVIUM.*

Workshop on eSTREAM Ciphers (Sep 30-Oct 1, 2011), Indian Statistical Institute, Delhi Centre, India, September 30, 2011.*Stream Ciphers: from One Time Pad to 4G.*

National Level Workshop on Cryptology (September 29-30, 2011) for College and University Teachers and Students, West Bengal State University, Barasat, India, September 29, 2011.*How to Send Secret Messages in Public.*

NAMSAA Popular Talk Series, New Alipore Multipurpose School, Kolkata, India, September 24, 2011.*Partial State Exposure of HC-128 and Its Consequences.*

Indo-Japan Joint Workshop on Cryptography, Indian Statistical Institute, Kolkata, India, September 15, 2011.*Random Number Generation and Stream Cipher.*

Tutorial Workshop on Cryptology, Rajabazar Science College Campus, University of Calcutta, India; jointly organized by the University of Calcutta & the Centre of Excellence in Cryptology, Indian Statistical Institute, July 16, 2011.*Wireless Encryption Algorithms.*

UGC Refresher Course for College and University Teachers on Security in Wired and Wireless Networks, School of Mobile Computing and Communication, Jadavpur University, Kolkata, India, July 14, 2011.*Randomness and Cryptography.*

Seminar organized by Computer Chapter of IEEE Calcutta Section, School of Mobile Computing and Communication, Jadavpur University, Kolkata, India, July 13, 2011.*Cryptology: The Art and Science of Secure Communication.*

Workshop on Emerging Technology in Computing, June 8, 2011, St. Thomas’ College of Engineering & Technology, Kolkata, India.*Fundamentals of Stream Ciphers.*

National Level Instructional Workshop on Cryptology (May 9-13, 2011), Centre for Cyber Security, Amrita Vishya Vidyapeetham, Coimbatore, India, May 11, 2011.*Cryptosystems and Cryptanalytic Attacks.*

Training on Information and Network Security, Scientific Analysis Group (SAG), Defence Research & Development Organisation (DRDO), Delhi, Ministry of Defence, Govt. of India, February 4, 2011.*Symmetric Key Cryptography: Some Modern Stream Ciphers.*

BARC Lecture Series on Cryptology, Supercomputing Facility, Computer Division, Bhabha Atomic Research Centre (BARC), Mumbai, India, November 23, 2010.*State of the Art Software Stream Ciphers.*

National Level Instructional Workshop on Cryptology (for University and College Teachers of the North-East Region, May 5-7, 2010), Department of Mathematics, Manipur University, Imphal, India, May 6, 2010..**Construction of Full State from Half State of HC-128**

Seminar at Coding & Cryptography Research Group (CCRG), Division of Mathematical Sciences, School of Physical & Mathematical Sciences, Nanyang Technological University (NTU), Singapore, March 10, 2010.*New Distinguishing Attacks on HC-128.*

Security Fundamentals (SF) Meeting, Research Center for Information Security (RCIS), National Institute of Advanced Industrial Science and Technology (AIST), Akihabara Site, Tokyo, Japan, July 13, 2009.*Stream Cipher RC4: A Case Study.*

Workshop on Teaching Cryptology at Undergraduate Level, Indian Statistical Institute (ISI), Kolkata, India; jointly organized by the Cryptology Research Society of India (CRSI) and the Institute of Mathematical Sciences (IMSc), Chennai, India; partially sponsored by Department of Science and Technology (DST), Government of India, June 18, 2009.*Recent Advances in RC4 Cryptanalysis.*

Workshop on Cryptography, Institute of Mathematics and Applications (IMA), Bhubaneswar; co-organized by the National Institute of Science Education and Research (NISER), Bhubaneswar (an Autonomous Institution of Department of Atomic Energy, Government of India); sponsored by the Science and Technology Department, State Council on Science and Technology, Government of Orissa and Institute of Mathematical Sciences (IMSc), Chennai, India, December 6, 2008.*Cryptology: A Technical Overview.*

Seminar at TwoPiRadian Infotech Private Limited (http://www.2pirad.com), Kolkata, India, February 2, 2008.**On New Weaknesses of the RC4 Stream Cipher**.

Centre for Applied Cryptographic Research (CACR) Seminar Series, University of Waterloo, Ontario, Canada, August 22, 2007.*Structural Weakness of the Key Scheduling of RC4.*

1st Indo-French Workshop on Cryptography and Related Topics (IFW), Paris, France, organized by the Indo-French Centre for the Promotion of Advanced Research under the Department of Science and Technology (DST), Government of India and the Ministry of Foreign Affairs, Government of France, June 11, 2007.*Basics of Public Key Cryptography.*

State Level Seminar on Application of Cryptology in Industry and Cryptanalysis (ACIC), Science City, Kolkata, India, organized by the Department of Information Technology of the RCC Institute of Information Technology and Partially Sponsored by Cognizant Technology Solutions (CTS), May 5, 2007.

##### Invited Talks on Mathematics

**A Refresher on Probability.**

Special Talk for Summer Internship in Cryptology (May 15 – July 7, 2017), Indian Statistical Institute (ISI), Kolkata, India, May 15, 2017.**Power and Limitations of Mathematical Logic.**

MathSpectrum – Symposium on varied flavours of mathematics for college teachers of any discipline, organized by Netaji Nagar College for Women, Kolkata, India, March 30, 2017.**Applications of Finite Fields.**

UGC Sponsored Refresher Course for College and University Teachers on Mathematics and Its Applications (Jan 02 – Jan 21, 2017), Department of Mathematics, Jadavpur University, Kolkata, India, January 21, 2017.**Theory of Finite Fields.**

UGC Sponsored Refresher Course for College and University Teachers on Mathematics and Its Applications (Jan 02 – Jan 21, 2017), Department of Mathematics, Jadavpur University, Kolkata, India, January 20, 2017.**Application of Mathematics in Science and Technology.**

Workshop on Mathematics-Cryptology-Computer Science for Higher Secondary students of (i) Jadavpur Sammilita Balika Vidyalaya, (ii) Lake Gardens School, (iii) Better High School and (iv) New Alipore Multipurpose School, organized by Netaji Nagar College for Women, Kolkata, India, December 8, 2016.**Mathematics for Computer Science.**

One-day State-Level Workshop on Mathematics, Computer Science and Cryptology, Department of Mathematics, Brahmananda Keshab Chandra (BKC) College, Kolkata, India, November 8, 2016.**Mathematical and Statistical Foundations of Cryptology and Security.**

Seminar for one-week academic visit to Indian Statistical Institute, Kolkata, India, by the students of Mathematics (Hons) and Statistics (Hons) of Ramnarain Ruia College, Mumbai, India, organized by Machine Intelligence Unit (MIU), Indian Statistical Institute (ISI), Kolkata, India, September 9, 2016.**Surprising Mathematics in Nature.**

Public Seminar at Netaji Nagar College for Women, Kolkata, India, March 30, 2016.**Mathematics in Nature.**

One-Day Workshop on Interesting Mathematical Concepts for Non-Mathematicians, South Calcutta Girls’ College, Kolkata, India, December 1, 2015.

Click HERE to view / listen.*Modular Arithmetic in Block Ciphers.*

Course on Cryptography, Department of Computer Science & Engineering, Tripura Institute of Technology (TIT), Agartala, India, November 7, 2014.*Statistics in Cryptology.*

Seminar for one-week visit to Indian Statistical Institute, Kolkata, India, by the students of Post Graduate Diploma in Statistical Methods with Applications, Indian Statistical Institute North East Centre, Tezpur, Applied Statistics Unit (ASU), Indian Statistical Institute (ISI), Kolkata, India, December 7, 2011.*Theory of Metrics.*

Seminar at Centre for Distributed Computing, Jadavpur University, Kolkata, India, January 21, 2011.*Algebraic Inequalities.*

Training program for the Regional Mathematical Olympiad (RMO) 2008 qualified candidates (West Bengal Region), Indian Statistical Institute, Kolkata, India, December 29, 2008.

##### Invited Talks on Computer Science

**Consensus Protocols in Blockchain Technology.**

Workshop on Crypto Currency organized by Andhra Pradesh Electronics and Information Technology Agency (APEITA), an autonomous society of Government of Andhra Pradesh, Visakhapatnam, India, April 22, 2017.**Keyless Dynamic Optimal Multibit Data Hiding in Energetic Pixels.**

India-Japanese Workshop on Cryptographic Techniques for Cyber Security (Feb 13-14, 2017), Department of Computer Science and Engineering, Indian Institute of Technology Roorkee, India, February 13, 2017.**Introduction to Time Complexity Analysis of Algorithms.**

Workshop on Mathematics-Cryptology-Computer Science for Higher Secondary students of A. K. Ghosh Memorial School and Khanpur (Boys) High School, organized by Netaji Nagar College for Women, Kolkata, India, September 26, 2016.**Algorithms — Correctness, Efficiency and Optimality.**

Workshop on Mathematics-Cryptology-Computer Science for Higher Secondary students of Kamala Girls’ High School and Harinavi Subhasini Balika Sikshalaya, organized by Netaji Nagar College for Women, Kolkata, India, September 21, 2016.**Computer Science in Cryptology.**

Workshop on Mathematics, Computer Science and Cryptology, Vivekananda College, Thakurpukur, Kolkata, India, September 14, 2016.**Problem-Solving in Computer and Algorithmic Thinking.**

One-Day Workshop on Cryptology, Mathematics and Theoretical Computer Science for Higher Secondary students of Jadavpur Vidyapith, organized by Netaji Nagar College for Women, Kolkata, India, January 27, 2016.**State-of-the-Art Research Areas in Computer Science.**

Seminar at Jadavpur University, organized by Jadavpur University Linux Users Group for all undergraduate engineering students of all colleges, Jadavpur University, Kolkata, India, August 26, 2015.

Click HERE to view / listen.**Introduction to Google Summer of Code.**

Inaugural speech at an awareness program for Google Summer of Code, organized by Jadavpur University Linux Users Group in association with Google Student Ambassador – India, Jadavpur University, Kolkata, India, March 24, 2015.*Automata Theory and Its Applications.*

Faculty Training Program at Bengal Institute of Technology (Techno-India Group of Colleges), Kolkata, India, December 20, 2013.*Introduction to Information and Coding Theory.*

UGC Refresher Course for College and University Teachers on Theoretical Aspects of Computer Science, Department of Computer Science & Engineering, Jadavpur University, Kolkata, India, February 5, 2009.*On Analysis and Design of Algorithms.*

UGC Refresher Course for College and University Teachers on Theoretical Aspects of Computer Science, Department of Computer Science & Engineering, Jadavpur University, Kolkata, India, February 6, 2009.*Propositional and Predicate Logic in Computer Science.*

UGC Refresher Course for College and University Teachers on Theoretical Aspects of Computer Science, Department of Computer Science & Engineering, Jadavpur University, Kolkata, India, February 9, 2009.*Introduction to Artificial Intelligence and Its Applications in Robotics.*

Robotics Workshop, St. Thomas’ College of Engineering & Technology, Kolkata, India, July 9, 2007.

##### Invited Talks on Education

*Teaching as a Way of Learning.*

2nd Sharing Knowledge, Insights, and Lessons Learned (SKILL) Conference, SUNY Albany; organized by the Center for Excellence in Teaching and Learning (CETL), SUNY Albany, U.S.A., October 16, 2004.**Beyond Data and Digits: My Teaching Experiences in the CSI Department.**

1st Sharing Knowledge, Insights, and Lessons Learned (SKILL) Conference, SUNY Albany; organized by the Center for Excellence in Teaching and Learning (CETL), SUNY Albany, U.S.A., November 1, 2003.