The successor to the SHA-1 algorithm (Secure Hashing Algorithm). SHA-1 could only produce a message digest (hash value) of 160 bits, providing no more than 80 bits of security against collision attacks. For the U.S. Advanced Encryption Standard, which uses keys of 128, 192 or 256-bit size, the newer SHA-2 algorithm (which contains the SHA-256, SHA-384 and SHA-512 sub-algorithms) was proposed, because it can produce hash sizes of 256, 384 or 512-bits with collision protection levels of 128, 192 and 256-bits respectively, thus balancing the security of the hash algorithm with that of the encryption algorithm.