Mastering Blockchain - Second Edition

Secure Hash Algorithms

The following list describes the most common Secure Hash Algorithms (SHAs):

• SHA-0: This is a 160-bit function introduced by NIST in 1993.
• SHA-1: SHA-1 was introduced in 1995 by NIST as a replacement for SHA-0. This is also a 160-bit hash function. SHA-1 is used commonly in SSL and TLS implementations. It should be noted that SHA-1 is now considered insecure, and it is being deprecated by certificate authorities. Its usage is discouraged in any new implementations.
• SHA-2: This category includes four functions defined by the number of bits of the hash: SHA-224, SHA-256, SHA-384, and SHA-512.

• SHA-3: This is the latest family of SHA functions. SHA-3-224, SHA-3-256, SHA-3-384, and SHA-3-512 are members of this family. ...