From ancient ciphers to blockchain: how cryptography guards your digital world

Have you ever wondered why no one can steal your information during online payments? Why only you and the other party can see messages in instant messaging? The secret lies in the ancient yet modern science of cryptography.

From protecting national secrets and bank transactions to safeguarding cryptocurrencies and smart contracts, cryptography has become the unsung hero of the digital world. This article will take you deep into the full picture of cryptography: tracing its history, dissecting how modern algorithms work, revealing its applications in daily life, and exploring exciting future developments.

What exactly is cryptography? A simple explanation for you

Many people confuse cryptography with encryption, but in fact, its scope is much broader. It’s not just about hiding information, but a comprehensive science about ensuring information security.

Core concepts: the four main tasks of cryptography

Imagine you want to send a secret to a friend—how can you ensure no one else looks at it along the way? That’s what cryptography is for.

Cryptography (from Greek κρυπτός meaning “hidden”, γράφω meaning “write”) is a set of methods to ensure data security. Its main goals include:

• Confidentiality: ensuring only authorized persons can read the information. Your encrypted message should be meaningless to eavesdroppers.

• Data integrity: ensuring information isn’t tampered with during transmission or storage, whether accidentally or maliciously.

• Authentication: confirming the message is from the genuine sender, not an imposter.

• Non-repudiation: the sender cannot deny having sent a message or completed a transaction afterward.

In today’s digital age, without cryptography, online banking would be dangerous, government communications would be exposed, the entire foundation of blockchain technology would collapse, and encrypted assets like Bitcoin would lose their meaning.

Cryptography is everywhere, but you might not notice

Cryptography is like air—it works silently behind the scenes:

• Secure website connections: The small lock icon in your browser’s address bar indicates HTTPS, protected by TLS/SSL encryption protocols. When you log in, pay, or input sensitive info, everything is encrypted.

• Instant messaging apps: Signal, WhatsApp, and Telegram use “end-to-end encryption” to ensure only you and your conversation partner can read messages.

• Email: PGP and S/MIME protocols allow you to encrypt email content and add digital signatures.

• Wireless networks: Home and office Wi-Fi use WPA2/WPA3 protocols with cryptography to prevent unauthorized access.

• Bank cards: EMV chip cards verify card authenticity and secure transactions using cryptographic algorithms.

• Online payments and transfers: Banks, payment systems, and financial platforms rely on multiple layers of cryptographic protection.

• Electronic signatures: Used to prove document authenticity and author identity.

• Cryptocurrencies and blockchain: From Bitcoin to Ethereum, these systems are built on cryptographic hash functions and digital signatures to ensure tamper-proof and transparent transactions.

• Data protection: Encryption of hard drives, databases, and files prevents information leaks.

• Virtual Private Networks (VPNs): Encrypt your internet traffic to protect privacy on public networks.

Don’t confuse cryptography with encryption

These two terms are often used interchangeably, but they have important differences:

Encryption is a specific process: converting readable information (plaintext) into unreadable form (ciphertext) using algorithms and keys, and reversing it with decryption.

Cryptography is a broader discipline that includes:

• Design and analysis of encryption algorithms
• Cryptanalysis: the science of breaking cryptosystems
• Protocols: designing secure communication rules (like TLS/SSL)
• Key management: securely generating, distributing, storing, and discarding keys
• Hash functions: creating “digital fingerprints” to verify integrity
• Digital signatures: proving authorship and data integrity

In short, encryption is the most famous tool within cryptography, but the field encompasses much more.

How cryptography evolved from ancient times to today

The story of cryptography spans thousands of years—from simple letter substitutions to complex mathematical algorithms.

From early ideas to modern complexity

Ancient world: The earliest examples appeared in ancient Egypt (~1900 BC), where they used non-standard hieroglyphs to hide messages. The Spartans (5th century BC) invented the Scytale—a wooden rod of a specific diameter, with messages written on parchment wrapped around it; only a rod of the same diameter could read the message.

Classical and medieval periods: Caesar cipher (1st century BC) was a simple shift cipher but could confuse those unaware of the technique. Arab scholars (like Al-Kindi in the 9th century) pioneered “frequency analysis”—cracking simple substitution ciphers by analyzing letter frequency. The Vigenère cipher (16th century) used a keyword to generate polyalphabetic substitutions and was once considered unbreakable (“le chiffre indéchiffrable” in French).

World wars: The advent of telegraphy spurred more complex ciphers. During WWI, the British cryptanalysts cracked the Zimmermann Telegram, influencing U.S. entry into the war. WWII was a golden age for cryptography. Germany’s Enigma machine was an electromechanical cipher device producing highly complex polyalphabetic substitutions. Polish mathematicians and British scientists (including Alan Turing at Bletchley Park) cracked it, significantly impacting the war. Japan’s “Purple” machine was also deciphered by the Americans.

Computer era: In 1949, Claude Shannon published “A Mathematical Theory of Communication,” laying the foundation for modern cryptography. In the 1970s, DES (Data Encryption Standard) became the first widely adopted symmetric encryption standard. In 1976, Whitfield Diffie and Martin Hellman introduced public-key cryptography, revolutionizing secure communication. The RSA algorithm (by Rivest, Shamir, and Adleman) was developed and remains widely used today.

The stories of classic ciphers

Scytale: a transposition cipher relying on the rod’s diameter. Can be broken by brute-force.

Caesar cipher: each letter shifted by a fixed number. Up to 32 variants in the Russian alphabet. Easy to crack via brute-force or frequency analysis.

Vigenère cipher: uses a keyword to determine shifts. More resistant than simple substitution but cracked by Charles Babbage and Friedrich Kasiski in the 19th century.

Enigma machine: an electromechanical device with rotors, switchboards, and reflectors. Each keystroke produces a different substitution. Cracking it required enormous computational effort and ingenuity.

From mechanical to digital: the big shift in cryptography

Classical cryptography relied on mechanical devices and manual operations; modern cryptography uses mathematics and computational power.

Key turning points include:

Mathematical foundations: Shannon’s work provided a rigorous mathematical framework.

Standardization: DES and later AES standardized algorithms for broad application and compatibility.

Emergence of asymmetric cryptography: The public key concept solved a fundamental problem—how to securely exchange keys over insecure channels—paving the way for e-commerce, digital signatures, and HTTPS.

Computational explosion: Enabled the use of more complex, stronger algorithms but also threatened older cryptosystems.

Core methods and algorithms of cryptography

Modern cryptography is built on complex mathematical algorithms, generally categorized as follows:

Symmetric vs asymmetric encryption

These are two fundamentally different approaches:

How do they work together?

In practice, a hybrid approach is used: first, asymmetric cryptography securely exchanges a symmetric key, then that key encrypts large data quickly. This is how HTTPS/TLS works.

Hash functions: the “digital fingerprint” of data

Hash functions are special mathematical functions that convert input data of any length into a fixed-length output (hash value, digest, or “digital fingerprint”).

Key features:

• One-way: nearly impossible to reverse from hash to original data.
• Deterministic: same input always yields same hash.
• Collision-resistant: hard to find two different inputs producing the same hash (weak and strong resistance).
• Avalanche effect: small input changes cause drastic hash changes.

Uses:

• Verifying data integrity (comparing hashes after download)
• Secure password storage (storing hashes instead of plaintext passwords)
• Digital signatures (signing hash of documents)
• Blockchain (linking blocks, generating wallet addresses)

Common algorithms:

MD5 (deprecated and insecure), SHA-1 (deprecated), SHA-2 family (SHA-256, SHA-512) (widely used), SHA-3 (new standard), GOST R 34.11-2012 (“Streebog”).

The crisis and response in the quantum era

Quantum computers (if realized) threaten most modern asymmetric algorithms (RSA, ECC) because these rely on the difficulty of factoring or discrete logarithms. Quantum algorithms (Shor’s algorithm) can crack them efficiently.

Responses include:

Post-quantum cryptography (PQC): developing new algorithms resistant to both classical and quantum attacks, based on different hard problems (lattices, codes, hashes, multivariate equations). Currently undergoing standardization efforts (e.g., NIST competition).

Quantum cryptography: not using quantum computers, but quantum mechanics principles to protect information. Quantum Key Distribution (QKD) allows two parties to establish shared secret keys securely; any eavesdropping alters quantum states and is detectable. QKD is operational and tested in pilot projects.

The future of quantum cryptography and PQC is promising, ensuring data security in the quantum computing age.

Cryptography vs steganography: two ways of hiding

These concepts are often confused:

Cryptography hides the content of information, making it unreadable, but the existence of encrypted data is visible.

Steganography (from Greek στεγανός meaning “hidden” + γράφω “write”) hides the existence of information. Secret data is concealed within innocuous media like images, audio, video, or plain text.

These techniques can be combined: encrypt first, then hide within a carrier, creating double-layer protection.

Applications of cryptography in today’s world

Cryptography has become the backbone of digital infrastructure, protecting everything from daily communication to financial systems.

Internet and communication security

TLS/SSL (Transport Layer Security)

The foundation of HTTPS. When you see “https://” and a lock icon, TLS/SSL is working:

1. Server identity verification (via certificates)
2. Secure key exchange (often using RSA or ECC)
3. Symmetric encryption (like AES) encrypts all data, protecting login info, passwords, credit card data, etc.

End-to-end encryption (E2EE)

Used in Signal, WhatsApp, Threema. Messages are encrypted on sender’s device and decrypted only on receiver’s device. Even service providers cannot see content. Usually implemented with a combination of symmetric and asymmetric encryption.

DNS encryption

DoH (DNS over HTTPS) and DoT (DNS over TLS) encrypt DNS queries, preventing ISPs or observers from seeing which sites you visit.

Secure email

PGP and S/MIME enable email encryption and digital signatures, ensuring confidentiality and sender authenticity.

Digital signatures and financial security

Digital signatures

A cryptographic mechanism to verify authenticity and integrity of electronic documents. How it works:

1. Generate hash of the file
2. Sign the hash with the sender’s private key (creating the signature)
3. Recipient uses sender’s public key to verify the signature and compare hash

If matching, the document is authentic and unaltered.

Use cases: legal documents, submitting reports to authorities, electronic procurement, transaction confirmation.

Financial sector cryptographic defenses

Online banking

Uses TLS/SSL for sessions, encrypts customer databases, employs multi-factor authentication with cryptographic elements.

Bank cards (EMV chips)

Cards contain cryptographic keys; perform encryption operations to authenticate with banks and terminals, preventing cloning.

Payment systems

Visa, Mastercard, etc., use complex cryptographic protocols for authorization and data protection.

ATMs

Encrypted communication with processing centers, PIN encryption at storage.

Crypto assets and blockchain pillars

For digital asset traders, understanding cryptography is essential. Blockchain is fundamentally built on cryptographic hash functions and digital signatures. Bitcoin and other cryptocurrencies use these mechanisms to ensure tamper-proof transactions, address security, and transparent history.

Always choose trading platforms that employ advanced cryptographic protections to safeguard your wallets, private keys, and transaction data.

Enterprises and government agencies

Data protection

Encrypt databases, files, and sensitive documents (storage and transmission). Prevent leaks, comply with regulations (GDPR, etc.).

Internal communication

Use VPNs for secure remote access, encrypt corporate emails and instant messaging.

Document management

Electronic Document Management Systems (EDMS) with digital signatures give legal validity and authenticity.

Government communication

Use certified cryptographic tools for confidential communication.

Access control

Use cryptographic methods (tokens, smart cards) for user authentication and authorization.

Russian enterprise applications

In Russia, popular enterprise software like “1C:Enterprise” often integrates Cryptographic Information Protection Tools (CIPM) such as CryptoPro CSP or VipNet CSP because:

Electronic reporting: Submissions to tax (FNS), pension (PFR), social security (FSS) agencies require digital signatures.

Electronic document flow (EDF): Exchanging legally significant documents (invoices, acts, contracts) with partners needs electronic signatures.

Government procurement: Participation in electronic procurement platforms (ETP) requires digital signatures.

Data security: Some 1C configurations support encrypting databases or specific records with cryptographic tools.

This integration allows enterprises to meet legal and security standards directly within familiar systems.

Global cryptography landscape

Cryptography development and regulation vary across countries, but international cooperation and trends are important.

Contributions and standards in Russia

Russia has a strong cryptography tradition rooted in Soviet-era mathematics.

National standards (GOST)

Russia’s national cryptography standards include:

• GOST R 34.12-2015: symmetric block cipher standard, includes “Kuznetschik” (128-bit) and “Magma” (64-bit) algorithms.
• GOST R 34.10-2012: elliptic curve digital signature standard.
• GOST R 34.11-2012: hash function standard “Streebog” (hash length 256 or 512 bits).

Used for government systems, handling state secrets, and interactions with government agencies.

Regulatory bodies

FSB (Federal Security Service) oversees licensing, production, sale, and maintenance of cryptographic tools, certifying their security.

FSTEC (Federal Service for Technical and Export Control) manages technical information protection, closely related to cryptography.

Local developers

Russian companies like CryptoPro, InfoTeKS, and Code of Security develop cryptography security solutions.

USA’s global influence

The US has historically led in cryptography.

NIST (National Institute of Standards and Technology) standardizes algorithms (DES, AES, SHA series) and is now leading post-quantum cryptography standards.

NSA (National Security Agency) has historically developed and analyzed cryptography, sometimes raising concerns about influence on standards.

Academia and industry: US universities and tech companies drive ongoing cryptography innovation.

Europe’s independent approach

ENISA promotes security best practices and standards.

GDPR (General Data Protection Regulation) emphasizes data protection; while not specifying algorithms, encryption is a key measure.

Germany, France, UK, and others have strong national cybersecurity centers and cryptography traditions.

China’s technological independence

China pursues self-reliance in cryptography, developing its own algorithms (SM2, SM3, SM4).

Cryptography use is tightly regulated by the government.

Invests heavily in quantum and post-quantum cryptography R&D.

International standards framework

Besides national standards, international bodies set norms:

ISO/IEC develops info tech and security standards, including encryption (ISO/IEC 18033), message authentication codes (ISO/IEC 9797), key management (ISO/IEC 11770).

IETF (Internet Engineering Task Force) creates internet standards, including cryptographic protocols (TLS, IPsec, PGP).

IEEE (Institute of Electrical and Electronics Engineers) standardizes cryptography in network tech (e.g., Wi-Fi standards).

International standards ensure global communication and commerce system compatibility and trust.

Making cryptography a profession

As digital technology penetrates society, demand for cryptography and information security specialists continues to grow.

Careers and essential skills

Professionals working in cryptography have multiple career paths:

Cryptographer (researcher)

Designs new algorithms and protocols, analyzes their strength, researches post-quantum cryptography. Requires strong math background (number theory, algebra, probability, complexity).

Cryptanalyst

Analyzes and breaks existing cryptosystems. Works defensively (finding vulnerabilities) or in specialized agencies.

Information security engineer / cybersecurity specialist

Applies cryptographic tools to protect systems and data. Implements, configures cryptography systems, VPNs, PKI, key management, security monitoring.

Secure software developer

Understands cryptography and how to properly use cryptographic libraries/APIs to write secure applications.

Penetration tester

Finds vulnerabilities, including cryptographic misuses, to fix them.

Essential skills

• Solid math foundation
• Understanding of cryptographic algorithms and protocols
• Programming skills (Python, C++, Java)
• Network and OS knowledge
• Analytical thinking, problem-solving
• Attention to detail
• Continuous learning (the field evolves rapidly)

Learning paths

University and degrees

Top universities worldwide (MIT, Stanford, ETH Zurich, EPFL, Technion) have strong cryptography and cybersecurity programs.

Online platforms

Coursera, edX, Udacity offer courses from top universities and professors.

Career opportunities

The cybersecurity and cryptography field offers diverse career paths:

Industries: IT companies, fintech (banks, payment systems, digital assets), telecom, government, defense, consulting (security audits, pentesting), any digitizing enterprise.

Advancement: From junior engineers to senior experts, security managers, architects, consultants, or research roles.

Market demand: High and growing, driven by increasing cyber threats and digital transformation.

Salary levels: Generally above average IT salaries, especially for experts with deep cryptography knowledge.

This is a dynamic field full of intellectual challenges and career prospects, requiring ongoing development but offering interesting work and good growth opportunities.

Summary: How cryptography shapes the future

Cryptography is not just a collection of complex formulas; it’s the foundational technology for trust and security, vital in an increasingly digital world.

From protecting personal emails and financial transactions to supporting government systems and frontier technologies like blockchain, cryptography’s influence is everywhere. We traced its evolution from ancient substitution ciphers to quantum computing, analyzed key methods and algorithms, and discussed its applications in Russia and globally.

For anyone wanting to securely handle their digital life, mastering cryptography basics is essential; for cybersecurity professionals, it’s a core skill.

Cryptography’s development never stops. New challenges (quantum computers) and solutions (post-quantum algorithms, quantum key distribution) are emerging constantly. This tech field will continue shaping a safer digital future.

We hope this article helped you better understand the world of cryptography and its importance. Safeguard your digital security, and adopt best practices when participating online.

FAQs

What to do if cryptography errors occur?

“Cryptography error” is a general message that can appear in many situations (handling digital signatures, connecting to websites, using cryptographic hardware). Causes vary, such as certificate issues (expired).

Recommended steps:

1. Restart the app or computer
2. Check certificate expiration date and status
3. Update cryptographic hardware, browsers, OS
4. Follow hardware instructions to check configuration
5. Try a different browser
6. Consult software documentation or contact tech support

If it’s a digital signature issue, contact the issuing certification authority.

What is a cryptographic module?

A cryptographic module is a hardware or software component designed specifically to perform cryptographic operations. Functions include encryption, decryption, key generation, hashing, digital signing, and verification.

How can students learn cryptography? What resources are available?

Start with history: Caesar cipher, Vigenère cipher are good for understanding basic principles.

Practice solving puzzles: Platforms like CryptoHack, Capture The Flag (CTF) competitions.

Popular books: “The Code Book” by Simon Singh, “Applied Cryptography” by Bruce Schneier (more advanced).

Visit museums: Cryptography museums or exhibitions if possible.

Mathematics: Master algebra, number theory, probability.

Coding: Implement simple ciphers (Caesar, Vigenère) in any programming language.

Online courses: Coursera, Stepik, edX offer beginner-friendly cryptography courses.