Departure question
Read signals from chancePort 11 of 11Travel from dice and insurance to data, noise, and learning algorithms—measuring uncertainty and turning it into decisions.
This voyage is an editorial path for understanding, not a claim of direct historical influence or sole invention.
Design confidentiality, integrity, and authentication so that only holders of the right keys can perform the required operations. RSA is one public-key scheme relying on the classical difficulty of factoring large integers. HTTPS, finance, and messengers combine public-key methods, symmetric encryption, hashes, certificates, and careful implementation. A sufficiently large fault-tolerant quantum computer could use Shor's algorithm against RSA and classical ECC, motivating migration to post-quantum standards.
Year | Cipher | Underlying hard mathematical problem | Broken? |
|---|---|---|---|
BCE 50 | Caesar cipher | None (simple shift) | ✗ Frequency analysis |
1553/1586 | Bellaso/Vigenère-style polyalphabetic cipher | Repeated keys and obscured frequencies | ✗ Kasiski, 1863, and other attacks |
1918–1940s | Enigma | Rotors, wiring, and plugboard settings | ✗ Polish Cipher Bureau and Bletchley Park teams |
1976 | Diffie-Hellman | Discrete logarithms are hard | ✓ against classical computers / ✗ against quantum computers (Shor) |
1977 | RSA | Factoring a product of large primes is hard | ✓ against classical computers / ✗ against quantum computers (Shor) |
1985 | ECC (elliptic curves) | Elliptic-curve discrete logarithm | ✓ against classical computers / ✗ against quantum computers |
2024+ | Post-quantum ML-KEM and ML-DSA | Lattice problems | Believed secure against known quantum attacks; standardized by NIST |
Cryptographic security depends not only on hardness assumptions but also on parameters, protocols, implementation, and key management. Quantum risk is driving a staged transition from RSA/ECC toward hybrid and post-quantum systems.
The mathematics of secrets — from Caesar ciphers to quantum key distribution. Information security is fundamentally a question of which math is hard.
Ports in time
Follow the scenes to see problems, notation, standards of proof, and applications changing across different times and places.
Julius Caesar used a fixed shift of the alphabet for military communication — one of the simplest substitution ciphers.
No reliable place is given, so time continues without an invented pin
Continue through the world of this yearClaude Shannon’s work made information measurable in bits, laying the mathematical foundation for digital compression and communication.
No reliable place is given, so time continues without an invented pin
Continue through the world of this yearTwo parties could now agree on a secret over a channel that everyone could observe — a starting point for modern internet security.
No reliable place is given, so time continues without an invented pin
Continue through the world of this yearPeter Shor found a quantum algorithm for factoring large integers efficiently, revealing a future threat to RSA and accelerating research into post-quantum cryptography.
No reliable place is given, so time continues without an invented pin
Continue through the world of this yearHTTPS, SSH, encrypted messaging, blockchain signatures, password hashing, and zero-knowledge proofs — the trust infrastructure of digital society.
Curated sources and problems. Bring one discovery back from OEIS, Project Euler, MathOverflow, or arXiv.
No concept belongs to one person
These are not inventor credits. They are different ports: opening a problem, sharpening a language, or carrying it into another world.
Number lenses
These numbers are editorial lenses for the voyage, not required prerequisites.
Travel from dice and insurance to data, noise, and learning algorithms—measuring uncertainty and turning it into decisions.
Open the number voyage
Travel from dice and insurance to data, noise, and learning algorithms—measuring uncertainty and turning it into decisions.
Open the number voyage
Travel from dice and insurance to data, noise, and learning algorithms—measuring uncertainty and turning it into decisions.
Open the number voyage
Concept genealogy
Concepts arriving from before
Current port
Cryptography and Information
Concepts opened from here
No direct successor port is curated yet.
Only direct editorial links are shown; this is not a complete learning order or historical influence line.
