cryptography

Hash functions

Cryptography

Posted on September 15, 2020 | 6 minutes | 1068 words | Iulian Costan

In simple terms, hash functions transform input data of arbitrary size (e.g. text, binary, etc) to fixed-length output (called hash value, hash code, fingerprint, message digest or simply hash) in a deterministic way. [Read More]

cryptography hash digest mdc mac preimage collision

Commitment schemes

Cryptography

Posted on February 25, 2020 | 8 minutes | 1639 words | Iulian Costan

A cryptographic commitment scheme is a way of committing to a statement without revealing the statement itself or reveal it at a later time. [Read More]

cryptography commitment scheme pedersen elgamal elliptic-curve

Elliptic curves

Cryptography

Posted on September 25, 2019 | 5 minutes | 1030 words | Iulian Costan

The easiest way to understand Elliptic Curve (EC), point addition, scalar multiplication and trapdoor function; explained with simple graphs and animations. [Read More]

cryptography elliptic-curve math sagemath python

Zero-knowledge proofs

Cryptography

Posted on August 26, 2019 | 7 minutes | 1481 words | Iulian Costan

Zero-knowledge is a method to prove that you know a secret ``x`` (e.g. a password, private key, piece of knowledge, etc) without revealing that secret. [Read More]

cryptography zero-knowledge-proof math python zcash

Zero-knowledge proofs

Cryptography

Posted on August 26, 2019 | 7 minutes | 1416 words | Iulian Costan

— layout: post title: "Zero-knowledge proofs" subtitle: Cryptography date: 2019-08-26 tags: ["cryptography", "zero-knowledge-proof", "math", "python", "zcash"] — [Read More]

cryptography zero-knowledge-proof python math

EC-Schnorr

Cryptography

Posted on June 25, 2019 | 4 minutes | 662 words | Iulian Costan

Overview EC-Schnorr, as the name suggests, is a Schnorr-type digital signature scheme over elliptic curve, it's ECDSA's little sister and Schnorr's big brother implemented in the upcoming MuSig in Bitcoin. [Read More]

cryptography schnorr ellipticcurve math python sagemath

Schnorr

Cryptography

Posted on June 19, 2019 | 3 minutes | 556 words | Iulian Costan

Schnorr is another digital signature scheme known for its simplicity, no division, no inversion, just plain old multiplication. [Read More]

cryptography schnorr discrete-logarithm math sagemath

ECDSA

Cryptography

Posted on April 9, 2019 | 4 minutes | 818 words | Iulian Costan

Elliptic curve cryptography (ECC) and digital signature algorithm (ECDSA) are more complex than RSA or ElGamal but I will try my best to hide the hairy math and the implementation details. [Read More]

cryptography ecdsa discrete-logarithm math eli5 python sagemath

ElGamal

Cryptography

Posted on March 26, 2019 | 4 minutes | 816 words | Iulian Costan

ElGamal is a public key cryptosystem that is used in encryption , digital signature and homomorphic cryptography. [Read More]

cryptography elgamal discrete-logarithm math eli5 python

RSA

Cryptography

Posted on March 16, 2019 | 4 minutes | 803 words | Iulian Costan

RSA (Rivest-Shamir-Adleman) needs no introduction, it is well known and most used public-key cryptosystem that governs our digital lives. [Read More]

cryptography rsa factorization math eli5