Is initialization vector needed for decryption?

Is initialization vector needed for decryption?

It is recommended that an Initialization vector be random and used only once meaning it will some how need to be send to the receiver which seems identical to the proposal of generating a random first block of plaintext and discarding it after decryption.

Are initialization vectors secret?

4 Answers. An initialization vector needs not be secret (it is not a key) but it needs not be public either (sender and receiver must know it, but it is not necessary that the Queen of England also knows it).

How do I decrypt a Gnupg file?

The decryption process is the same.

1. Open the file manager.
2. Navigate to the encrypted file.
3. Right-click the encrypted file.
4. Click Open with Decrypt File.
5. When prompted, give the new file a name and click Enter.
6. When prompted, enter the decryption password and click Enter.

When to use a random initialization vector in cryptography?

It is recommended that an Initialization vector be random and used only once meaning it will some how need to be send to the receiver which seems identical to the proposal of generating a random first block of plaintext and discarding it after decryption. Thanks for contributing an answer to Cryptography Stack Exchange!

Do you need the IV to decrypt a block?

However, you do not need the IV to decrypt subsequent blocks. You could perform CBC in a way that would remove the need to know the initialization vector (note: this is not recommended or encouraged, just pointing it out for the novelty).

Do you need to know the initialization vector for CBC?

You could perform CBC in a way that would remove the need to know the initialization vector (note: this is not recommended or encouraged, just pointing it out for the novelty). If you use a null IV and use a random value for the first block of plaintext, you can discard this value and only transmit the ciphertext.

How does AES decrypt the first block of bytes?

Can’t it just decrypt it, drop the first x amount of bytes and then it has the original plaintext or does AES do some special jizz-jazz with the first bytes in the stream? The initialization vector is XORed against the first plaintext block before encryption in CBC mode, as shown in the Wikipedia article on block cipher modes.