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Is IV secret?
IV usually does not need to be secret, However, in most cases, it is important that an initialization vector is never reused under the same key. Wikipedia: An initialization vector has different security requirements than a key, so the IV usually does not need to be secret.
What is an IV key?
An initialization vector (IV) is an arbitrary number that can be used along with a secret key for data encryption. This number, also called a nonce, is employed only one time in any session. The IV length is usually comparable to the length of the encryption key or block of the cipher in use.
What is nonce AES?
AES-CCM generates two outputs: a ciphertext and a message authentication code (also called an authentication tag). The nonce is generated by the party performing the authenticated encryption operation. Within the scope of any authenticated- encryption key, the nonce value MUST be unique.
Do we need to encrypt IV?
The important thing about an IV is you must never use the same IV for two messages. Cryptography is a subtle art. I would save the IV in the data file, as it does not harm security as long as the IV is random/unique.
When do you use IV and salt in encryption?
They serve the same purpose, but are technically used in different operations. Salt is used when hashing, IV when encrypting. In both cases, the purpose is to prevent the same input from always resulting in the same output by adding a random input. If you see ‘salt’ in context of encryption, it probably means IV.
Why is it insecure to use a randomized IV for CBC-MAC?
Why is it insecure to use a randomized IV for CBC-MAC instead of an all-zero IV? A fixed length CBC-MAC uses an all-zero block as the initialization vector. Suppose that we used a randomized IV instead, and sent the IV along with the tag.
Do you need a key for symmetric encryption?
The symmetric encryption classes supplied by the .NET Framework require a key and a new initialization vector (IV) to encrypt and decrypt data. Whenever you create a new instance of one of the managed symmetric cryptographic classes using the parameterless constructor, a new key and IV are automatically created.
When do you use a salt and when an IV?
The code isn’t screwing up, but rather it’s using the salt while hashing then later using an IV while encrypting. Many people conflate the terms ‘salt’ and ‘initialization vector’. They serve the same purpose, but are technically used in different operations. Salt is used when hashing, IV when encrypting.