Digital Security Resilience: How Cryptography Protects Our Online Environment

Have you ever wondered why your online wallet remains secure and how the bank server knows that the payment transaction is made by the right person? The answer lies in the deep principles of cryptography. Today, as digital companies and personal data are constantly under threat, this ancient science has become our key to security.

Cryptography Definition: Simply Put

Cryptography is not just about hiding information – it is a comprehensive scientific discipline that involves ensuring data confidentiality, integrity, authenticity, and non-repudiation.

Imagine you can send a secret message to a friend in such a way that no one else can read it. You can create a cipher – for example, replacing each letter with another. This is the beginning of cryptography. More theoretically, the term cryptography comes from ancient Greek (κρυπτός – hidden, γράφω – to write) and signifies achieving data security through transformation.

Four main objectives:

• Confidentiality – data is readable only to authorized persons
• Integrity – information remains unaltered during transmission and storage
• Authentication – the source of information can be verified
• Non-repudiation – the sender cannot deny having done it

Where Cryptography Intersects Our Lives

Cryptography is an invisible but underlying force:

Secure website (HTTPS): When you see a padlock icon in the URL bar, TLS/SSL is working – encrypting traffic between you and the server. Your passwords, payment details, and personal data remain hidden.

Messaging apps: Signal, WhatsApp, and others use end-to-end encryption. Even the app provider cannot read messages.

Email: PGP and S/MIME enable encrypting messages and documents, and digitally signing them.

WiFi networks: WPA2/WPA3 protocols hide your connection at home and in the office.

Bank cards and payments: Every PIN code, every transfer amount is protected cryptographically.

Cryptocurrencies: The blockchain directly depends on cryptography – hash functions and digital signatures.

Cryptography vs Encryption: Why the Difference Matters

These terms are often confused, but the difference is significant:

Encryption is a process – transforming plaintext into unreadable cipher and vice versa.

Cryptography is a science that includes:

• Developing and analyzing encryption algorithms
• Cryptanalysis (methods for breaking ciphers)
• Developing secure protocols
• Key management systems
• Hash function theory
• Digital signature methods

Thus, encryption is a part of cryptography, not the entire field.

The Historical Journey of Cryptography

From Ancient Times to Central Europe

Earlier traces of encryption are found in Ancient Egypt (around 1900 BC), where non-standard hieroglyphs were used. In Ancient Sparta (5th century BC), the scytale was common – a rod of a certain diameter wrapped with a strip of text. To read the message, the same diameter rod was needed.

Caesar cipher (1st century BC) shifts each letter by a fixed number – simple but effective for its time.

Arab scholars, especially Al-Kindi (9th century), proposed frequency analysis – a method to break simpler substitution ciphers by counting letter frequencies.

Vigenère cipher (16th century) used a keyword, changing the shift at each step. For nearly three centuries, it was considered “unbreakable.”

Mechanical and Electronic Era

During World War I, cryptography was already important. British researchers broke the “Zimmermann telegram,” influencing the US entry into the war.

In World War II, mechanical cryptography dominated. The German Enigma machine was perfect for its time – with rotors, electrical circuits, and reflectors. Its decryption by British mathematicians at Bletchley Park (led by Alan Turing) was a decisive moment in the battle.

The Computer Revolution

In 1949, Claude Shannon published “A Mathematical Theory of Communication,” laying a mathematical foundation for cryptography.

The DES (Data Encryption Standard) of the 1970s was the first internationally recognized symmetric encryption standard.

In 1976, Diffie and Hellman launched public key cryptography – a revolutionary idea that two parties can have different keys.

RSA algorithm (Rivest, Shamir, Adleman) implemented this theory in practice and remains in use today.

Symmetric vs Asymmetric: Two Paths to Security

Symmetric Cryptography

One secret key encrypts and decrypts. Like a lock and key – whoever has the key can open the lock.

Advantages: Fast, suitable for large data volumes. Disadvantages: Secure key distribution is complex. Each pair of partners needs its own key.

Examples: AES (modern standard), DES, 3DES.

Asymmetric Cryptography

Two mathematically related keys – public (everyone knows) and private (only the owner knows). Like a mailbox – anyone can insert a message (public key), but only the owner can read it with the (private key).

Advantages: Solves key distribution problem. Enables digital signatures and cryptocurrencies. Disadvantages: Significantly slower than symmetric. Not suitable for large files.

Examples: RSA, ECC (elliptic curves – more modern, efficient).

In practice, a hybrid approach is often used: asymmetric cryptography exchanges the key, then symmetric encrypts the data. This is how HTTPS/TLS works.

Hash Functions: Digital Fingerprints

A hash function transforms an input of any length into a fixed-length output – a “digital fingerprint.”

Properties:

• One-way: Reversing the process is practically impossible.
• Convenient: Same input always yields the same hash.
• Collision-resistant: Two different inputs do not produce the same hash.
• Avalanche effect: Small input changes drastically change the hash.

Uses:

• File integrity check (downloaded file vs public hash)
• Password storage (store hash, not password)
• Blockchains (link blocks via hash)

Examples: SHA-256 (widely used), SHA-3, GOST R 34.11-2012 (Russian standard).

Quantum Computers: Future Threat and Countermeasures

Powerful quantum computers threaten current asymmetric algorithms (RSA, ECC), which rely on the difficulty of factoring large numbers.

Countermeasures:

Post-quantum cryptography (PQC): New algorithms supporting quantum attacks. Fields: lattice structures, codes, hash functions. The NIST standardization process is ongoing.

Quantum key distribution (QKD): Using quantum mechanics for secure key exchange. Any eavesdropping attempt reveals itself as a change in the quantum state.

Applications of Cryptography: Real World

Internet and Messaging

TLS/SSL: Ensures a secure channel between you and the server. Certificates authenticate the domain, key exchanges encrypt traffic.

End-to-end encryption: Signal, WhatsApp, Threema – decrypted on the recipient’s device, the provider’s server cannot see the content.

DNS over HTTPS (DoH): Hides your website visits.

Banking and Finance

E-banking: Sessions are encrypted with TLS, multifactor authentication is used.

Bank cards (EMV): Chip encrypts data with the terminal, preventing cloning.

Payment systems: Visa, Mastercard – multi-layer encryption.

Crypto payments: Blockchain relies on hash functions and digital signatures.

Companies and Governments

Data protection: Encrypting sensitive data at rest and in transit.

Digital signatures: Authenticity and immutability of documents. Important in government procurement, courts, tax declarations.

VPNs: Secure remote access for employees.

Access control: Cryptographic tokens and smart cards.

Russia Specifics: 1C and GOST Systems

Russian companies use cryptographic protection modules (like CryptoPro CSP), especially:

• E-filing: For tax authorities, pension funds – requires qualified electronic signature.
• Electronic tenders: ETP platforms require signatures.
• Document exchange: Security of legally significant documents.

GOST standards (Russian federal):

• GOST R 34.12-2015: Symmetric algorithms (Kuznetschik, Magma)
• GOST R 34.10-2012: Digital signature (elliptic curves)
• GOST R 34.11-2012: Hash function (Streibog)

Regulators: FSB (issue licenses, inspections), FSTEC (monitor).

International Standards and Regulations

Russia’s Contribution

The Soviet mathematical tradition is strong. Today:

• State standards (GOST) for protecting state secrets
• Active research in post-quantum and quantum models
• Companies: CryptoPro, InfoTeKS, Security Code

USA and NIST

NIST is the global standards hub (for DES, AES, SHA). Currently, the post-quantum cryptography standard is being published.

With NSA’s involvement, caution is advised in analyzing standards.

Europe

GDPR requires adequate security measures – cryptography plays a key role.

ENISA promotes best practices.

China

Own standards (SM2, SM3, SM4) and strict regulation. Active investments in PQC and quantum fields.

International Bodies

ISO/IEC: Standards for information security.

IETF: Internet protocols (TLS, IPsec, PGP).

IEEE: Network standards.

Career in Cryptography

Demand for security specialists is growing.

Job Roles

Cryptographer: Developing new algorithms, analysis, post-quantum research. Requires deep mathematics (theory of computation, algebra, probability).

Cryptanalyst: Analyzing systems and finding vulnerabilities. For defense and intelligence agencies.

Information security engineer: Practical implementation of cryptographic solutions – VPNs, PKI, encryption systems.

Secure developer: Working with applications that use cryptographic libraries.

Penetration tester: Finding vulnerabilities, including cryptographic misuses.

Required Skills

• Fundamentals of mathematics
• Understanding algorithms and protocols
• Programming (Python, C++, Java)
• Network and operating system knowledge
• Analytical thinking
• Continuous learning (field evolves rapidly)

Learning Platforms

• Universities (MIT, Stanford, ETH Zurich)
• Online courses (Coursera, edX, Stepik)
• Books (Simon Singh “The Code Book”, Bruce Schneier “Applied Cryptography”)
• CTF competitions and CryptoHack

Summary

Cryptography is not abstract mathematics – it is the lifeblood of our digital world. From personal messages to government data, financial transactions to blockchain, everything relies on the strength of ciphers.

Its history was built from ancient star shifts to modern asymmetric algorithms. Quantum computers bring new threats, but PQC and QKD offer countermeasures.

Russia has a strong tradition and active development. International cooperation satisfies everyone.

Anyone wishing to navigate digital security must understand the basics of cryptography. And those aiming for a career in this field will find many opportunities, but require deep knowledge and continuous learning.

Use trusted platforms, monitor your digital footprint, and understand that unseen cryptography protects your back.