- Invited talk at the
**Amity University, Kolkata**on the topic#### Secure Digital Communication using Mathematical and Statistical Tools

on September 26, 2018. - Invited as an Invited Speaker at the
**105th Indian Science Congress in Mathematical Science Section (including Statistics)**held at Imphal, Manipur during March 16-20, 2018 and delivered an invited talk on#### Digital Data Security: Mathematical Aspects of Cryptography.

on March 18, 2018 - Invited as a resource person at the Faculty Development Programme on Cryptography and Networking Security (FDPCNS-2018) organized by the Dept. of Computer Science & Engineering,
**Jalpaiguri Govt. Engineering College**and delivered an invited talk on#### Secret Sharing Scheme: An Important Primitive for Cryptography

on March 14, 2018. - Invited as an invited Speaker at the Annual Seminar Lecture organized by the
**Department of Mathematics, Serampore College**, and delivered an invited talk on#### Applications of Algebra and Number Theory in Secure Digital Communications

on January 13, 2018 - Invited as a resource person at the Two-Day National Seminar on Contemporary Research in Theoretical and Applicable Mathematics organized, held during September 8-9, 2017 organized by the
**The Bhawanipur Education Society College**and delivered the invited lecture on#### Algebraic Aspects of Cryptology and its Application to Modern Cyber Security

on September 9, 2017. - Invited as a resource person at the “Short Term Course on Fundamental Algorithms: Design and Analysis" organized by the
**Department of Mathematics, IIT Kharagpur**and delivered an invited talk on#### Cryptographic Algorithms

on February 11, 2017. - Invited as a resource person at the Workshop on “Communications and Multimedia Security” organized by the
**Department of Computer Science and Engineering of IIT(ISM), Dhanbad**and delivered a n invited lecture on#### Visual Cryptography: A Different Secret Sharing Scheme

on February 10, 2017 - Invited as a resource person at the
**“TEQIP-II sponsored short term course on "Introduction to Cryptography" during 27-31 January, 2017**organized by the Department of Mathematics, IIT Kharagpur and delivered two invited talks on January 28, 2017. The title of the talks are:#### ❖ Evaluation of Secret Sharing Schemes.

#### ❖ Visual Cryptography: A Different Approach.

- Invited as a resource person at the Tutorial of the “Third International Conference on Mathematics and Computing (ICMC 2017)" during January 17-21, 2017 at Haldia, India organized by the Haldia Institute of Technology,
Haldia and delivered an invited lecture on
#### Few Aspects of Secret Sharing Schemes

on January 18, 2017. - Delivered a special lecture on
#### Applications of Mathematics in Securing Digital Data

on 14-12-2016 at the**City College, Kolkata**. - Delivered a special lecture on
#### Securing Digital World Through Mathematics

on 02-12-2016 at the**Bhairab Ganguly College, Kolkata** - Invited as a resource person at the Faculty Development Programme on “Preparing for Challenges in Higher Education Institutions" during September 23-29, 2016, organized by the
**Bhawanipur Education Society College**and delivered an invited lecture on#### Cryptology and Reading Numerical Codes

(on September 28, 2016). - Invited as a resource person at the UGC-Sponsored Seminar on “Basic Mathematics and its Applications" organised by
**RKMVC College, Rahara,**Kolkata on September 21, 2016 and delivered an invited lecture on#### Applications of Groups, Rings, Fields and Linear Algebra in Digital World

(on September 21, 2016). - Three invited lectures under UGC-SAP (DRS-II) at the
**Department of Mathematics and Statistics, University of Himachal Pradesh, Himachal**. The Title of the talks are as follows:#### Symmetric and Asymmetric Key Cryptography. (on May 28, 2016)

#### Applications of Cryptography. (on June 3, 2016)

#### Visual Cryptography.(on June 4, 2016)

- Invited talk on
#### Algebraic Aspects of A Special Type of Secret Sharing Scheme:Visual Cryptography

at the**Department of Mathematics, Shiv Nadar University, Uttar Pradesh**, on May 26, 2016. - Invited talk on
#### Linear Algebraic Aspects of Visual Cryptography: Few Open Issues

at the**Department of Mathematics, Cochin University of Science and Technology**, Kochi, Kerala on March 15, 2016. - Invited talk on
#### Future Prospects in Mathematics after UG and PG Courses in India and Foreign Countries

organized by the**Career and Counseling Cell of Barasat Govt. College, West Bangal**, on February 2, 2016. - Two invited talks on
#### Number theory and Algebra

at**Lady Brabourne College, West Bangal,**on October 23 and 30, 2015. - Invited talk on
#### Applications of Groups, Rings and Fields in the Digital World Through Cryptography

at the UGC Sponsored National Seminar on Recent Trends on Pure and Applied Mathematics, August 14, 2015, organized by the**Uluberia College, West Bangal.** - Invited as a resource person to the National Workshop on Cryptology 2014, during September 25-27, 2014, organized by
**PDPM IIITDM Jabalpur**and delivered the invited talk#### OR-Based Monotone and XOR-Based Non-Monotone Visual

on September 25, 2014. - Invited as a resource person to the short term course entitled "A Short Term Course on Cryptography" from 18th May, 2014 to 24th May, 2014 organized by the
**Department of Mathematics, IIT Kharagpur**and delivered the following two invited talks on#### Introduction to Secret Sharing.

#### Visual Cryptography and DNA Secret Sharing.

- Invited as a resource person to the workshop entitled "Instructional Workshop On Graph Theory And Its Applications To Visual Cryptography", during March 10-15, 2014, organized by the
**National Centre for Advanced Research in Discrete Mathematics**(n-CARDMATH), Kalasalingam University, Madurai and delivered the following four invited talks on#### Introduction to Visual Cryptography: A Very Different Cryptographic Scheme. (on March 10, 2014)

#### Mathematical and Statistical Tools to Study (2,n)-VCS (on March 10, 2014)

#### Cumulative Array and Linear Algebraic Techniques to Construct VCS for General Access Structure. (on March 11, 2014)

#### Color VCS and Future Direction of Research. (on March 11, 2014)

- Invited as a resource person to annual Program entitled "Analytica 2013", on September 25, 2013, organized by
**St Xavier's College, Kolkata**delivered the invited talk on#### Introduction to Algebraic Cryptography

. - Invited talk on
#### An Introduction to Mathematical Cryptography at the Department of Mathematics

, at**Lady Brabourne College, Kolkata**on May 17, 2012 - Invited talk on
#### Some Secret Sharing Schemes With Emphasis on Visual Cryptography

at the Seminar on Cryptography organized by the**Barasat State University,**on September 30, 2011. - Invited talk on
#### Some Secret Sharing Schemes and Further Studies

on July 16, 2011 at the Tutorial Workshop on Cryptology, July 16-17, 2011, organized by**University of Calcutta and COEC, ISI Kolkata.** - Invited as a resource person to deliver an invited talk on
#### Cryptography is the science of analyzing and deciphering codes, ciphers and cryptograms

at the**Engineer, Golden Jubilee Edition Technical Symposium of NITK Surathkal**, during 29 October to 1 November 2009. - Invited as a resource person to deliver an invited talk on
#### Introduction to Secret Sharing and Some Interesting Secret Sharing Schemes

at the**CRSI-IMSc Joint Workshop on Teaching Cryptology**at Undergraduate level during June 15-19, 2009 at the Indian Statistical Institute, Kolkata. - Invited talk on
#### Changing Faces of Terrorism and Importance of Cryptography

on the occasion of the Celebration of National Science Day, February 28, 2009, organized by**Indian Science Congress Association**. - Invited as a resource person to deliver an invited talk on
#### Visual and DNA cryptography

at the Workshop on Cryptography, December 5-6, 2008, organized by**Institute of Mathematics and Applications, Bhubaneswar.** - Invited as a resource person to deliver an invited talk on
#### Changing Faces of Terrorism and Secret Message Transmission

at the UGC sponsored Seminar on Changing Faces of Terrorism, a 21st Century Perspective, organized by**Gokhale Memorial Girls College, Kolkata.**