The iteration count is the number of times that the password is hashed during the derivation of the symmetric key. The higher number, the more difficult it is to validate a password guess and then derive the correct key. It is used together with the salt which is used to prevent against attacks using rainbow … Read more
Let us breakdown the word piece by piece: PBKDF2–WithHmac–SHA512 Let’s go over it part by part PBKDF2 Stands for Password-based-Key-Derivative-Function, a successor of PBKDF1 and is used to implement a pseudorandom function, such as a cryptographic hash, cipher, or HMAC to the input password or passphrase along with a salt value and repeats the process … Read more
In short, the reason for the difference is that PBKDF2 algorithm in modes #1 and #2 uses PKCS #5 v2 scheme 2 (PKCS5S2) for iterative key generation, but the BouncyCastle provider for “PBEWITHHMACSHA1” in mode #3 uses the PKCS #12 v1 (PKCS12) algorithm instead. These are completely different key-generation algorithms, so you get different results. … Read more