The latest articles, guides, and tutorials on cryptography and data security from Cipher Visualizers.https://laoutaris.cc/https://laoutaris.cc/blog/ascon_guide/https://laoutaris.cc/blog/ascon_guide/In August 2025, NIST standardized a cipher small enough to run on a battery-powered sensor and simple enough to fit its whole state in five CPU registers. Learn how Ascon's sponge-based permutation delivers real authenticated encryption at a fraction of AES-GCM's footprint.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/dilithium_guide/https://laoutaris.cc/blog/dilithium_guide/NIST's primary post-quantum signature standard works by signing, checking your own signature against a size limit, and throwing it away and starting over if it's too big. Learn how 'Fiat-Shamir with Aborts' turns a leaky lattice proof into a secure signature.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/falcon_guide/https://laoutaris.cc/blog/falcon_guide/Falcon produces the smallest signatures of any NIST post-quantum standard — by solving a problem that broke the leading lattice signature schemes of the late 1990s/early 2000s. Learn the hash-and-sign paradigm, and why the naive version of it is fatally insecure.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/frodokem_guide/https://laoutaris.cc/blog/frodokem_guide/FrodoKEM deliberately throws away the algebraic structure that makes lattice cryptography fast — trading performance for a security proof that rests on plain, 'vanilla' Learning With Errors. Learn how it works and why some cryptographers prefer that trade.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/hqc_guide/https://laoutaris.cc/blog/hqc_guide/In March 2025, NIST picked a second code-based algorithm to back up Kyber — one that hides its noise completely differently from McEliece. Learn how HQC masks a public, unscrambled code with pure algebraic randomness instead.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/kyber_guide/https://laoutaris.cc/blog/kyber_guide/The key encapsulation mechanism NIST chose to replace RSA and ECDH for general-purpose use. Learn how Kyber hides a noisy linear system inside a polynomial ring to get both lattice-hard security and real-world speed.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/ntru_guide/https://laoutaris.cc/blog/ntru_guide/Before Kyber, before LWE was even named, NTRU showed that ordinary polynomial multiplication in the right ring could resist quantum attacks. Learn how NTRU hides a fast decryption trick behind a public convolution product.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/rainbow_guide/https://laoutaris.cc/blog/rainbow_guide/Rainbow signed messages using polynomial equations so tangled that solving them looks impossible — until, in 2022, someone found a shortcut and broke it in a weekend on a laptop. Learn how it worked, and how it fell.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/saber_guide/https://laoutaris.cc/blog/saber_guide/SABER reached the final round of NIST's post-quantum competition with a trick Kyber doesn't use: instead of adding random noise, it rounds numbers down and lets the rounding error itself do the job. Learn how Learning With Rounding works.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/sphincs_guide/https://laoutaris.cc/blog/sphincs_guide/Every other post-quantum signature scheme bets on a new hard math problem holding up. SPHINCS+ makes almost no new bet at all — its security rests on nothing but hash functions. Learn how a tree of one-time signatures becomes a full signature scheme.Wed, 05 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/3des_guide/https://laoutaris.cc/blog/3des_guide/When DES's 56-bit key became too weak, the industry didn't design a new cipher from scratch — it just ran DES three times. Learn how Triple DES extended the life of the original standard for another two decades.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/aes_gcm_guide/https://laoutaris.cc/blog/aes_gcm_guide/AES-GCM does two jobs at once: it hides your data AND proves nobody tampered with it. Learn how Galois/Counter Mode combines AES with GHASH authentication to become the default choice for TLS, IPsec, and disk encryption.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/aes_guide/https://laoutaris.cc/blog/aes_guide/AES is the encryption algorithm that secures nearly everything: HTTPS traffic, encrypted disks, messaging apps, and government secrets alike. This comprehensive guide breaks down exactly how the Rijndael cipher transforms data, round by round.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/argon2_guide/https://laoutaris.cc/blog/argon2_guide/Argon2 won the 2015 Password Hashing Competition by making brute-force attacks expensive in RAM, not just CPU time — closing off the GPU and ASIC cracking farms that broke older schemes. Here's how memory-hardness works.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/blowfish_guide/https://laoutaris.cc/blog/blowfish_guide/Bruce Schneier designed Blowfish as a free, fast alternative to DES, with a distinctive twist: its own S-boxes are generated from the encryption key itself. Learn how it works and why it's still found in legacy systems today.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/chacha20_poly1305_guide/https://laoutaris.cc/blog/chacha20_poly1305_guide/TLS 1.3's second mandatory cipher suite pairs ChaCha20 encryption with the Poly1305 message authenticator, delivering AES-GCM-equivalent security without needing any special hardware. Here's how the pairing works.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/cmac_guide/https://laoutaris.cc/blog/cmac_guide/What if you already have AES in your system and don't want to bring in a separate hash function just for message authentication? CMAC builds a MAC directly from a block cipher instead.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/des_guide/https://laoutaris.cc/blog/des_guide/The Data Encryption Standard ruled cryptography for over two decades. Learn how its Feistel network works, why its 56-bit key ultimately doomed it, and why it still matters as the foundation for 3DES and AES.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/dsa_guide/https://laoutaris.cc/blog/dsa_guide/DSA was the U.S. government's answer to a simple question: how do you prove a message came from you, without RSA's patent? Learn how the Digital Signature Algorithm works, and why a single reused number sank Sony's PS3 security.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/hkdf_guide/https://laoutaris.cc/blog/hkdf_guide/TLS 1.3 and the Signal Protocol both lean on the same small, elegant primitive to turn a shared secret into however many separate keys they actually need. Here's how HKDF's extract-then-expand design works.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/hmac_guide/https://laoutaris.cc/blog/hmac_guide/A hash alone can't prove a message wasn't tampered with — anyone can recompute it. HMAC fixes that by mixing in a secret key, becoming one of the most quietly essential building blocks in TLS, SSH, and beyond.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/idea_guide/https://laoutaris.cc/blog/idea_guide/IDEA was one of the first ciphers to mix three completely different mathematical operations within a single round. Learn how this Swiss-designed algorithm became a mainstay of early PGP, and why it eventually gave way to AES.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/mceliece_guide/https://laoutaris.cc/blog/mceliece_guide/McEliece has survived over 45 years of cryptanalysis without ever being broken — and it's one of NIST's chosen post-quantum standards. Learn how hiding an error-correcting code behind scrambling matrices creates a public-key system quantum computers can't crack.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/paillier_guide/https://laoutaris.cc/blog/paillier_guide/What if you could add two numbers together without ever decrypting them? Paillier encryption makes that possible — the mathematical trick behind private vote tallying and secure multi-party computation.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/pbkdf2_guide/https://laoutaris.cc/blog/pbkdf2_guide/For nearly two decades, PBKDF2's answer to password cracking was simple: make every guess expensive by repeating a hash thousands of times. Here's how it works, and why memory-hard successors like Argon2 eventually surpassed it.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/rc4_guide/https://laoutaris.cc/blog/rc4_guide/RC4 was the simplest, fastest cipher of its era — powering SSL, WEP, and WPA for over a decade before a decade of accumulating bias attacks quietly killed it. Learn how it works and exactly why it's insecure today.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/rsa_guide/https://laoutaris.cc/blog/rsa_guide/RSA is the algorithm that made public-key cryptography practical for the world. This comprehensive guide explores how RSA works, why it's secure, where it's used, and where it's headed as quantum computing looms.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/salsa20_chacha_guide/https://laoutaris.cc/blog/salsa20_chacha_guide/Designed by Daniel J. Bernstein as a fast, secure, RC4-free alternative for software encryption, ChaCha20 now secures TLS 1.3 and WireGuard alike. Learn how its add-rotate-XOR "quarter round" builds a full cipher from pure arithmetic.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/schnorr_guide/https://laoutaris.cc/blog/schnorr_guide/Schnorr signatures are what DSA might have been if a 20-year patent hadn't gotten in the way. Simpler, provably secure, and now at the heart of Bitcoin's Taproot upgrade — here's how they work.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/shake_guide/https://laoutaris.cc/blog/shake_guide/Most hash functions give you a fixed-size output no matter what you ask for. SHAKE breaks that rule — it's a hash function you can ask for any amount of output from, built from the same Keccak sponge as SHA-3.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/twofish_guide/https://laoutaris.cc/blog/twofish_guide/Twofish was Bruce Schneier's answer to Blowfish's biggest weakness — and one of the five finalists in the competition that ultimately chose AES. Learn how its Feistel network, PHT mixing, and key-dependent S-boxes work.Tue, 04 Aug 2026 00:00:00 GMThttps://laoutaris.cc/blog/dh_guide/https://laoutaris.cc/blog/dh_guide/The Diffie-Hellman key exchange stands as one of the most revolutionary breakthroughs in modern cryptography, fundamentally changing how secure communications are established across insecure networks.Sun, 27 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/ecc_guide/https://laoutaris.cc/blog/ecc_guide/Elliptic Curve Cryptography (ECC) is a powerful and efficient form of public-key cryptography that leverages the mathematical properties of elliptic curves over finite fields.Sun, 27 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/elgamal/https://laoutaris.cc/blog/elgamal/ElGamal Encryption: A Comprehensive Guide to Public-Key CryptographySat, 26 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/eddsa/https://laoutaris.cc/blog/eddsa/The Edwards-curve Digital Signature Algorithm (EdDSA) is a modern public-key signature scheme that has gained significant traction in the world of cryptography for its high levels of security and efficiency.Fri, 25 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/tls-protocol/https://laoutaris.cc/blog/tls-protocol/Understanding TLS: The Backbone of Secure Internet CommunicationFri, 25 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/signal/https://laoutaris.cc/blog/signal/The Signal Protocol is a modern, open-source cryptographic protocol that provides end-to-end encryption for voice calls, video calls, and instant messaging conversations.Thu, 24 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/pgp-hybrid/https://laoutaris.cc/blog/pgp-hybrid/Understanding Pretty Good Privacy: Hybrid Encryption for Secure Messaging and DataSun, 20 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/blake23-hash/https://laoutaris.cc/blog/blake23-hash/BLAKE2 and BLAKE3 have emerged as the preferred choice for new applications requiring high-performance hashingSat, 19 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/sha1-hash/https://laoutaris.cc/blog/sha1-hash/Secure Hash Algorithm 1 was for years one of the most widely used cryptographic hash functions. Fri, 18 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/sha2-hash/https://laoutaris.cc/blog/sha2-hash/The SHA-2 family of cryptographic hash functions is the gold standard for digital security today.Fri, 18 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/sha3-hash/https://laoutaris.cc/blog/sha3-hash/SHA-3, also known as **Keccak** (pronounced 'ketchak'), is the newest member of the Secure Hash Algorithm family standardized by NIST.Fri, 18 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/md5-hash/https://laoutaris.cc/blog/md5-hash/The MD5 represents a pivotal moment in cryptographic historyWed, 16 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/hill-cipher/https://laoutaris.cc/blog/hill-cipher/Learn about Mathematical Elegance in Classical CryptographyTue, 15 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/playfair-cipher/https://laoutaris.cc/blog/playfair-cipher/The Playfair Cipher: A Complete Educational GuideTue, 15 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/railfence-cipher/https://laoutaris.cc/blog/railfence-cipher/Learn about Mathematical Elegance in Classical CryptographyTue, 15 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/caesar_breaker_guide/https://laoutaris.cc/blog/caesar_breaker_guide/Breaking the Caesar Cipher: A Python Journey from Comprehensive to ConciseMon, 14 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/vigenere-cipher/https://laoutaris.cc/blog/vigenere-cipher/The Vigenère Cipher: A Journey Through History and Modern Applications.Mon, 14 Jul 2025 00:00:00 GMThttps://laoutaris.cc/blog/caesar-cipher/https://laoutaris.cc/blog/caesar-cipher/Learn about one of the simplest and most widely known encryption techniques, the Caesar cipher.Mon, 07 Jul 2025 00:00:00 GMT