This course is designed to give you a solid foundation in how information is protected in the digital age. Step into the world of cryptography—the science behind secure communication. This course aims to prepare you for an exciting and in-depth journey into the world of modern cryptography. Designed for undergraduate students, it introduces the core principles, mathematical foundations, and practical applications that make secure digital communication possible today. You will start by learning the basics of cryptographic systems, including classical ciphers (block and stream), modular arithmetic, and finite fields—tools that form the backbone of encryption.

Cryptography
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Recommended experience
Recommended experience
Intermediate level
Learners should have an understanding of the basics of computer networks and fundamental networking concepts.
Recommended experience
Recommended experience
Intermediate level
Learners should have an understanding of the basics of computer networks and fundamental networking concepts.
What you'll learn
Understand various cryptographic and network security services and mechanisms
Apply various cryptographic techniques and system-level network security applications
Analyse various cryptographic techniques and system-level network security applications
Evaluate the cryptographic algorithms, hash algorithms and network application security schemes
Details to know

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May 2026
93 assignments
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There are 10 modules in this course
Cryptographic principles are the fundamental concepts and techniques that are used in the field of cryptography to secure communication and protect data. These principles include confidentiality, integrity, authentication, non-repudiation, and key management. Students will grasp how cryptography protects our digital world. We will start with its purpose — turning sensitive data into unreadable formats to keep it safe. Then, we will break down the key principles: confidentiality, integrity, and authentication. We will uncover the essential security services — like access control and non-repudiation. You will learn what they do and why they are crucial for any secure system. We will also explore the mechanisms that make it all work: encryption, hashing, and more.
What's included
13 videos10 readings9 assignments
13 videos•Total 88 minutes
- Course Introduction•3 minutes
- Meet Your Instructor: Prof. Pradnya Kashikar•2 minutes
- Meet Your Instructor: Prof. Rajesh Kumar•1 minute
- Basics of Information Security•8 minutes
- Basic Terminology•9 minutes
- CIA Triad - 1 •13 minutes
- CIA Triad - 2•8 minutes
- CIA Triad - 3•8 minutes
- Services and Mechanisms•4 minutes
- Security Policy•8 minutes
- Security Mechanisms•8 minutes
- Security Models•12 minutes
- Module Wrap Up Video•3 minutes
10 readings•Total 155 minutes
- Course Overview•20 minutes
- Recommended Reading: Basics of Information Security•15 minutes
- Recommended Reading: Basic Terminology •15 minutes
- Recommended Reading: CIA Triad - 1 •15 minutes
- Recommended Reading: CIA Triad - 2•15 minutes
- Recommended Reading: CIA Triad - 3•15 minutes
- Recommended Reading: Service and Mechanisms•15 minutes
- Recommended Reading: Security Policy •15 minutes
- Recommended Reading: Security Mechanisms•15 minutes
- Recommended Reading: Security Models•15 minutes
9 assignments•Total 51 minutes
- Basics of Information Security•3 minutes
- Basic Terminology•6 minutes
- CIA Triad - 1•6 minutes
- CIA Triad - 2•6 minutes
- CIA Triad - 3•6 minutes
- Services and Mechanisms•6 minutes
- Security Policy•6 minutes
- Security Mechanisms•6 minutes
- Security Models•6 minutes
This module introduces students to the foundational techniques of classical cryptography, focusing on how information is transformed to ensure secure communication. Learners will begin by understanding the basic concepts of plain text (readable data) and cipher text (encrypted data), establishing the groundwork for how cryptographic systems operate. The module then explores substitution techniques, where symbols in the plaintext are replaced with other symbols to obscure meaning. Examples such as the Caesar cipher, monoalphabetic cipher, and Vigenère cipher will be studied to illustrate how substitution alters data while maintaining structure. Next, students will examine transposition techniques, which rearrange the positions of characters without changing the symbols themselves. Methods like the Rail Fence cipher and Columnar transposition will demonstrate how order manipulation enhances security.
What's included
13 videos12 readings13 assignments
13 videos•Total 76 minutes
- Basic Terminology•5 minutes
- Cryptoterms•3 minutes
- Cryptography Mechanisms•5 minutes
- Substitution Techniques•4 minutes
- Substitution Techniques - 1•7 minutes
- Substitution Techniques - 2•5 minutes
- Substitution Techniques - 3•4 minutes
- Transposition Techniques•6 minutes
- Transposition Techniques - 1•7 minutes
- Transposition Techniques - 2•8 minutes
- Encryption and Decryption•8 minutes
- Key Distribution and MIMT•12 minutes
- Module Wrap-Up Video•2 minutes
12 readings•Total 165 minutes
- Recommended Reading: Basic Terminology•15 minutes
- Recommended Reading: Cryptoterms•15 minutes
- Recommended Reading: Cryptography Mechanisms•15 minutes
- Recommended Reading: Substitution Techniques•15 minutes
- Recommended Reading: Substitution Techniques - 1•15 minutes
- Recommended Reading: Substitution Techniques - 2•15 minutes
- Recommended Reading: Substitution Techniques - 3•10 minutes
- Recommended Reading: Transposition Techniques•10 minutes
- Recommended Reading: Transposition Techniques - 1•10 minutes
- Recommended Reading: Transposition Techniques - 2•15 minutes
- Recommended Reading: Encryption and Decryption•15 minutes
- Recommended Reading: Key Distribution and MIMT•15 minutes
13 assignments•Total 165 minutes
- Basic Terminology•9 minutes
- Cryptoterms•9 minutes
- Cryptography Mechanisms•6 minutes
- Substitution Techniques•9 minutes
- Substitution Techniques - 1•9 minutes
- Substitution Techniques - 2•9 minutes
- Substitution Techniques - 3•9 minutes
- Transposition Techniques•9 minutes
- Transposition Techniques - 1•9 minutes
- Transposition Techniques - 2•9 minutes
- Encryption and Decryption•9 minutes
- Key Distribution and MIMT•9 minutes
- Graded Quiz - Week 1 and 2•60 minutes
This module introduces symmetric key cryptography and its role in securing data. Learners will explore commonly used symmetric encryption algorithms such as AES, DES, 3DES, and Blowfish, and examine block cipher modes of operation including ECB, CBC, CFB, OFB, and CTR. The module also focuses on the practical application of encryption and decryption using different modes, along with an analysis of security vulnerabilities, key management challenges, and real-world use cases of symmetric cryptographic systems.
What's included
5 videos4 readings4 assignments
5 videos•Total 31 minutes
- Introduction•4 minutes
- Algorithm Modes-1•9 minutes
- Algorithm Modes-2•7 minutes
- Algorithm Modes-3•7 minutes
- Module Wrap Up Video•3 minutes
4 readings•Total 55 minutes
- Recommended Reading: Introduction •10 minutes
- Recommended Reading: Algorithm Modes-1•15 minutes
- Recommended Reading: Algorithm Modes-2•15 minutes
- Recommended Reading: Algorithm Modes-3•15 minutes
4 assignments•Total 36 minutes
- Introduction•9 minutes
- Algorithm Modes-1•9 minutes
- Algorithm Modes-2•9 minutes
- Algorithm Modes-3•9 minutes
This module introduces symmetric key cryptography and the concept of shared secret keys. Learners will study classical encryption algorithms such as DES, Double DES, and Triple DES, and explore symmetric key encryption algorithms including IDEA, RC5, and modern standards such as AES and Blowfish. The module also compares block ciphers and stream ciphers through practical examples, and analyses the strengths, limitations, and real-world applications of symmetric encryption algorithms in secure systems.
What's included
6 videos5 readings6 assignments
6 videos•Total 58 minutes
- Introduction•5 minutes
- DES - 1•10 minutes
- DES - 2•16 minutes
- DES - 3•12 minutes
- IDEA, RC5, BLOWFISH and AES•14 minutes
- Module Wrap Up Video•2 minutes
5 readings•Total 65 minutes
- Recommended Reading: Introduction•5 minutes
- Recommended Reading: DES - 1•15 minutes
- Recommended Reading: DES - 2•15 minutes
- Recommended Reading: DES - 3•15 minutes
- Recommended Reading: IDEA_RC5_AES_BLOWFISH•15 minutes
6 assignments•Total 105 minutes
- Introduction•9 minutes
- DES - 1•9 minutes
- DES - 2•9 minutes
- DES - 3•9 minutes
- IDEA, RC5, BLOWFISH and AES•9 minutes
- Graded Quiz - Week 3 and 4•60 minutes
Asymmetric Key Cryptography, also known as Public Key Cryptography, is a cryptographic system that uses a pair of mathematically related keys — a public key for encryption and a private key for decryption. This module explores the underlying mathematical concepts, key generation, encryption and decryption processes, digital signatures, and the role of asymmetric cryptography in securing modern communication systems such as SSL/TLS and email encryption.
What's included
10 videos4 readings10 assignments
10 videos•Total 107 minutes
- Symmetric vs. Asymmetric Systems•7 minutes
- Definition and Characteristics of Asymmetric Cryptography•8 minutes
- Real-World Applications•7 minutes
- Euler’s Theorem and Totient Function•10 minutes
- Prime Numbers and GCD•16 minutes
- Primality Testing Methods•7 minutes
- The Chinese Remainder Theorem•27 minutes
- Definition and Relevance•6 minutes
- Computational Complexity in Cryptography•10 minutes
- One-Way and Trapdoor Functions•8 minutes
4 readings•Total 205 minutes
- Recommended Reading: Fundamentals of Asymmetric Cryptography•60 minutes
- Recommended Reading: Number Theory in Cryptography•75 minutes
- Recommended Reading: Primality Testing and Modular Arithmetic•60 minutes
- Recommended Reading: Discrete Logarithms and Security Foundations•10 minutes
10 assignments•Total 108 minutes
- Symmetric vs. Asymmetric Systems•9 minutes
- Definition and Characteristics of Asymmetric Cryptography•9 minutes
- Real-World Applications•9 minutes
- Euler’s Theorem and Totient Function•12 minutes
- Prime Numbers and GCD•12 minutes
- Primality Testing Methods•12 minutes
- The Chinese Remainder Theorem•12 minutes
- Definition and Relevance•9 minutes
- Computational Complexity in Cryptography•12 minutes
- One-Way and Trapdoor Functions•12 minutes
The Asymmetric Key Cryptography Algorithms module focuses on the study and implementation of major public key algorithms used to secure data and communications. It covers key algorithms such as RSA, Diffie-Hellman, ElGamal, and Elliptic Curve Cryptography (ECC), exploring their mathematical foundations, key generation processes, encryption and decryption mechanisms, and real-world applications in digital security. The module also examines the strengths, weaknesses, and performance considerations of each algorithm in various cryptographic contexts.
What's included
10 videos3 readings11 assignments
10 videos•Total 99 minutes
- RSA Overview and Historical Background •7 minutes
- RSA Key Generation Process•12 minutes
- RSA Encryption and Decryption•9 minutes
- Diffie-Hellman Key Exchange – Protocol and Security•18 minutes
- ElGamal Encryption System – Steps and Usage•14 minutes
- Introduction to Elliptic Curve Arithmetic•7 minutes
- ECC-Based Key Exchange•9 minutes
- Advantages of ECC Compared to RSA•5 minutes
- Pseudorandom Number Generation in Asymmetric Cryptography•9 minutes
- Comparison of RSA, DH, ElGamal, and ECC•8 minutes
3 readings•Total 210 minutes
- Recommended Reading: RSA Algorithm •60 minutes
- Recommended Reading: Diffie-Hellman and ElGamal Systems•75 minutes
- Recommended Reading: Elliptic Curve Cryptography (ECC) •75 minutes
11 assignments•Total 177 minutes
- RSA Overview and Historical Background•12 minutes
- RSA Key Generation Process •12 minutes
- RSA Encryption and Decryption•12 minutes
- Diffie-Hellman Key Exchange – Protocol and Security•12 minutes
- ElGamal Encryption System – Steps and Usage•12 minutes
- Introduction to Elliptic Curve Arithmetic•12 minutes
- ECC-Based Key Exchange•12 minutes
- Advantages of ECC Compared to RSA•9 minutes
- Pseudorandom Number Generation in Asymmetric Cryptography•12 minutes
- Comparison of RSA, DH, ElGamal, and ECC•12 minutes
- Graded Quiz - Week 5 and 6•60 minutes
The Public Key Infrastructure (PKI) module provides an in-depth understanding of the framework that enables secure electronic communication through the management of public-key encryption and digital certificates. This module explores the core components of PKI, including Certificate Authorities (CAs), Registration Authorities (RAs), digital certificates, certificate revocation, and trust models. It also discusses how PKI supports secure email, web authentication (SSL/TLS), code signing, and identity verification in modern networked environments.
What's included
12 videos4 readings12 assignments
12 videos•Total 97 minutes
- Definition and Purpose of PKI•6 minutes
- Components of PKI•7 minutes
- How PKI Works: High-Level Process•8 minutes
- PKI Trust Models•10 minutes
- Certificate Life Cycle Management•6 minutes
- Certificate Revocation Mechanisms•8 minutes
- Types of Certificates•7 minutes
- X.509 Certificate Format•7 minutes
- Certificate Chains and Path Validation•10 minutes
- Common PKI Challenges•10 minutes
- PKI Applications•8 minutes
- PKI in Emerging Technologies•9 minutes
4 readings•Total 270 minutes
- Recommended Reading: PKI Fundamentals•60 minutes
- Recommended Reading: PKI Trust Models and Life Cycles•75 minutes
- Recommended Reading: Types and Formats of Digital Certificates•75 minutes
- Recommended Reading: PKI Challenges and Emerging Applications•60 minutes
12 assignments•Total 165 minutes
- Definition and Purpose of PKI•12 minutes
- Components of PKI•12 minutes
- How PKI Works: High-Level Process•12 minutes
- PKI Trust Models•12 minutes
- Certificate Life Cycle Management•12 minutes
- Certificate Revocation Mechanisms•12 minutes
- Types of Certificates•12 minutes
- X.509 Certificate Format•12 minutes
- Certificate Chains and Path Validation•12 minutes
- Common PKI Challenges•21 minutes
- PKI Applications•15 minutes
- PKI in Emerging Technologies•21 minutes
This module introduces authentication and its role in securing digital systems. Learners will study password-based authentication methods and their limitations, and explore biometric techniques such as fingerprint, facial recognition, and iris-based authentication. The module also examines two-factor and multi-factor authentication, token-based approaches, single sign-on, certificate-based authentication, and Kerberos. Finally, learners will analyse the strengths, weaknesses, vulnerabilities, and real-world applications of different authentication techniques.
What's included
12 videos11 readings12 assignments
12 videos•Total 119 minutes
- Introduction•15 minutes
- Password Based Authentication Techniques•12 minutes
- Password Based Authentication Techniques - 2•12 minutes
- Two-Factor Authentication•12 minutes
- Multi-Factor Authentication•11 minutes
- Biometric Authentication Techniques•10 minutes
- Biometric Authentication Techniques - 2•14 minutes
- Authentication Tokens•9 minutes
- Single-Sign-On•7 minutes
- Certificate Based Authentication•6 minutes
- Kerberos•10 minutes
- Module Wrap Up Video•3 minutes
11 readings•Total 165 minutes
- Recommended Reading: Introduction•15 minutes
- Recommended Reading: Password-Based Authentication Techniques-1•15 minutes
- Recommended Reading: Password Based Authentication Techniques - 2•15 minutes
- Recommended Reading: Two-Factor Authentication•15 minutes
- Recommended Reading: Multi-Factor Authentication•15 minutes
- Recommended Reading: Biometric Authentication Techniques•15 minutes
- Recommended Reading: Biometric Authentication Techniques -2•15 minutes
- Recommended Reading: Authentication Tokens•15 minutes
- Recommended Reading: Single-Sign-On•15 minutes
- Recommended Reading: Certificate Based Authentication•15 minutes
- Recommended Reading: Kerberos•15 minutes
12 assignments•Total 159 minutes
- Introduction•9 minutes
- Password Based Authentication Techniques•9 minutes
- Password Based Authentication Techniques - 2•9 minutes
- Two-Factor Authentication•9 minutes
- Multi-Factor Authentication•9 minutes
- Biometric Authentication Techniques•9 minutes
- Biometric Authentication Techniques - 2•9 minutes
- Authentication Tokens•9 minutes
- Single-Sign-On•9 minutes
- Certificate Based Authentication•9 minutes
- Kerberos•9 minutes
- Graded Quiz -Week 7 and 8•60 minutes
This module introduces the fundamentals of Internet security and cryptography. Learners will examine common Internet security protocols, including HTTPS, SSL/TLS, IPsec, SSH, SFTP, Kerberos, and OAuth 2.0/OpenID Connect. The module further explores advanced topics such as email security using PGP and S/MIME, core elements of web security, common web security threats, best practices, and emerging trends. Additionally, learners will study network security mechanisms including firewalls, intrusion detection and prevention systems (IDS/IPS), and virtual private networks (VPNs), and evaluate their role in securing modern Internet-based systems.
What's included
9 videos8 readings8 assignments
9 videos•Total 95 minutes
- Introduction•7 minutes
- Internet Security Protocols - 1•17 minutes
- SSH, SFTP, Kerberos, OAuth•17 minutes
- Email Security•15 minutes
- Web Security•14 minutes
- Firewalls•9 minutes
- IDS/IPS•8 minutes
- VPN•6 minutes
- Module Wrap Up Video•2 minutes
8 readings•Total 115 minutes
- Recommended Reading: Introduction•15 minutes
- Recommended Reading: Internet Security Protocols - 1•15 minutes
- Recommended Reading: SSH, SFTP, Kerberos, OAuth•15 minutes
- Recommended Reading: Email Security•15 minutes
- Recommended Reading: Web Security•15 minutes
- Recommended Reading: Firewalls•15 minutes
- Recommended Reading: IDS and IPS•15 minutes
- Recommended Reading: VPN•10 minutes
8 assignments•Total 138 minutes
- Introduction•9 minutes
- Internet Security Protocols - 1•9 minutes
- SSH, SFTP, Kerberos, OAuth•18 minutes
- Email Security•18 minutes
- Web Security•18 minutes
- Firewalls•21 minutes
- IDS/IPS•24 minutes
- VPN (Virtual Private Network)•21 minutes
This module introduces modern cryptography and focuses on advanced cryptographic techniques designed to enable privacy, security, and trust in contemporary digital systems. Learners will explore secure multi-party computation, zero-knowledge proofs, fully homomorphic encryption, and oblivious RAM, along with functional encryption and private information retrieval. The module also examines symmetric searchable encryption and leakage-resilient cryptography, and concludes with applications of modern cryptography in secure voting and secure election systems.
What's included
8 videos8 readings8 assignments
8 videos•Total 67 minutes
- Introduction•15 minutes
- Secure Multi-Party Computation (MPC)•8 minutes
- Zero-Knowledge Proofs (ZKPs)•10 minutes
- FHE and ORAM•6 minutes
- Function Encryption and PIR•6 minutes
- Symmetric Searchable Encryption and Leakage-Resilient Cryptogarphy•7 minutes
- Secure Voting & Secure Elections•13 minutes
- Module Wrap Up Video•3 minutes
8 readings•Total 100 minutes
- Recommended Reading: Introduction•15 minutes
- Recommended Reading: Secure Multi-Party Computation (MPC)•15 minutes
- Recommended Reading: Zero-Knowledge Proofs (ZKPs)•15 minutes
- Recommended Reading: FHE and ORAM•10 minutes
- Recommended Reading: Function Encryption and PIR•10 minutes
- Recommended Reading: Symmetric Searchable Encryption and Leakage-Resilient Cryptogarphy•10 minutes
- Recommended Reading: Secure Voting & Secure Elections•15 minutes
- Course Summary•10 minutes
8 assignments•Total 186 minutes
- Introduction•15 minutes
- Secure Multi-Party Computation (MPC)•15 minutes
- Zero-Knowledge Proofs (ZKPs)•18 minutes
- FHE and ORAM•18 minutes
- Function Encryption and PIR•18 minutes
- Symmetric Searchable Encryption and Leakage-Resilient Cryptogarphy•18 minutes
- Secure Voting & Secure Elections•24 minutes
- Graded Quiz - Week 9 and 10•60 minutes
Build toward a degree
This course is part of the following degree program(s) offered by Birla Institute of Technology & Science, Pilani. If you are admitted and enroll, your completed coursework may count toward your degree learning and your progress can transfer with you.¹
Build toward a degree
This course is part of the following degree program(s) offered by Birla Institute of Technology & Science, Pilani. If you are admitted and enroll, your completed coursework may count toward your degree learning and your progress can transfer with you.¹
Birla Institute of Technology & Science, Pilani
Bachelor of Science in Computer Science
Degree · 3-6 years
¹Successful application and enrollment are required. Eligibility requirements apply. Each institution determines the number of credits recognized by completing this content that may count towards degree requirements, considering any existing credits you may have. Click on a specific course for more information.
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Offered by

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Birla Institute of Technology & Science, Pilani (BITS Pilani) is one of only ten private universities in India to be recognised as an Institute of Eminence by the Ministry of Human Resource Development, Government of India. It has been consistently ranked high by both governmental and private ranking agencies for its innovative processes and capabilities that have enabled it to impart quality education and emerge as the best private science and engineering institute in India. BITS Pilani has four international campuses in Pilani, Goa, Hyderabad, and Dubai, and has been offering bachelor's, master’s, and certificate programmes for over 58 years, helping to launch the careers for over 1,00,000 professionals.
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