Hashing Passwords – Python Cryptography Examples


Building a from-scratch server or using a lightweight framework is empowering. With that power comes responsibility, specifically the responsibility to securely store user’s passwords. Not understanding the security implications of password storage can lead to devastating breaches and leaks. If you are building an application and need to store user credentials, learn about hash functions. … Read more

Why is Exclusive Or (XOR) Important in Cryptography?

Why is Exclusive Or (XOR) Important in Cryptography

If you are getting into cryptography, or just trying to understand the fundamentals, you may have noticed that the exclusive-or (XOR) operation is used quite often, especially in ciphers. XOR is a simple bitwise operation that allows cryptographers to create strong encryption systems, and consequently is a fundamental building block of practically all modern ciphers. … Read more

Cryptography Trends And News Going Into 2020

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Quantum Computing Quantum computing may not be coming quite as fast as some in the field had certainly feared (or perhaps hoped). Google did, however, solve an impressive problem this year. They published a paper in Nature. It stated that their quantum processor solved a problem that, in contrast, a digital computer would take 10,000 … Read more

(Very) Basic Intro to The AES-256 Cipher

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AES stands for “Advanced Encryption Standard” and is a specification that has selected the Rijndael cipher as its symmetric key ciphering algorithm. AES encrypts a message with a private key and no one except the key holder can decrypt the message. This is useful for many reasons, but a good example is a laptop that … Read more

(Very) Basic Intro to Hash Functions (SHA-256, MD5, etc)

Hash functions are used to securely store passwords, find duplicate records, quickly store and retrieve data, among other useful computational tasks. As a practical example, all user passwords on Qvault are hashed using Bcrypt to ensure that if an attacker were ever to gain access to our database our user’s passwords wouldn’t be compromised. I … Read more

Cryptology, Cryptography, and Cryptanalysis – Get your Vocabulary Straight!


Many new developers are jumping right into coding (usually for those fat paychecks) without learning much about the history of Computer Science. People regarded Alan Turing as the father of Computer Science. He was first a cryptologist and mathematician. Then, he pioneered the field of CS in order to solve cryptological problems. In this article, … Read more

Creating and Remembering a Strong Passphrase

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We all have hundreds of online accounts. Ideally, as many of those accounts as possible have unique passwords. Unique passwords however present a difficult problem: No one can remember hundreds of strong passwords. To fix this problem, we created password managers. Now, all of our passwords are neatly stored in one place, encrypted by one … Read more

BIP 32 Watch-Only Wallets


Bitcoin improvement proposal 32 is, in my opinion, one of the most important BIPs we have. (Thanks Peter Wuille!) BIP 32 gave us Hierarchical Deterministic Wallets. That is, the ability to create a tree of keys from a single seed. In the early days of Bitcoin, each time a user wanted to receive new coins, … Read more