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The latest blog posts to take off on Hacker News. 850 posts.

Crypto & Blockchain
Any year
841

Bitcoin is not decentralized

Bitcoin was designed by Satoshi Nakamoto, and the primary client is developed by a bunch of folks at bitcoin.org . Do you care who these people are? In theory, you shouldn’t: all they do is develop an open source client for an open source protocol. Anyone else can develop their own client (and some people have) and no…

848

Encrypt-then-MAC

First things first: Why use a composition of encryption and MAC instead of a single primitive which achieves both? Because people are very good at writing bad code. In my experience on the FreeBSD security team, writing dozens of security advisories, there are three types of code which are especially prone to have…

849

Cryptographic Right Answers

Encrypting data: Use AES in CTR (Counter) mode, and append an HMAC . AES is about as standard as you can get, and has done a good job of resisting cryptologic attacks over the past decade. Using CTR mode avoids the weakness of ECB mode, the complex (and bug-prone) process of padding and unpadding of partial blocks (or…

850

Bcrypt is now obsolete

I am speaking today at BSDCan'09 about my work on the scrypt key derivation function. In the context of hardware brute-force attacks, scrypt is thousands of times more secure than existing "best practice" solutions such as bcrypt and PBKDF2; in fact, under reasonable assumptions it is provably as strong as possible…