SHA-2 uses blocks of which sizes?

SHA-2, which is a family of cryptographic hash functions, processes data in blocks that are 512 bits (or 64 bytes) in size. The confusion in the answer may arise from the specifics of bit size in terms of internal operations, which are generally conducted in 32-bit or 64-bit segments during hashing, depending on the specific algorithm variant (like SHA-256 or SHA-512).

However, the fundamental block size for all SHA-2 variants is 512 bits. Each of these blocks then goes through a series of computations that often utilize 32-bit words. Thus, the 32 and 64 bits mentioned in the answer reflect the operational architecture rather than the specific block size.

This aspect of the SHA-2 architecture emphasizes the differences in how various hashing algorithms handle data, and it underscores the necessity of understanding both the theoretical and practical aspects of their operation. In any cybersecurity context, knowing the block size and the operational dynamics of SHA-2 is important for implementing secure hashing procedures correctly.