SHA-2 is a family of cryptographic hash functions designed by the NSA and published by NIST in 2001. The family includes various output lengths (224, 256, 384, and 512 bits). The SHA-2 family will eventually be replaced by the winner of NIST's hash function competition.
It's been said that CRC-64 is bijective for a 64-bit block. It the corresponding statement true for SHA-2?
In terms of security strength, Is there any difference in using the SHA-256 algorithm vs using any random 256 bits of the output of the SHA-512 algorithm? Similarly, what is the security difference ...
I've come up with this little routine for doing encryption using the SHA-2 (in this case SHA-256) hash function. As such it is a block cipher with a 256 bit (32 byte) block size and an arbitrary key ...