AES Encryption - Key versus IV

Question

The application I am working on lets the user encrypt files. The files could be of any format (spreadsheet, document, presentation, etc.).

For the specified input fi

Answer 1

IV is used for increase the security via randomness, but that does not mean it is used by all algorithm, i.e.

The trick thing is how long should the IV be? Usually it is the same size as the block size, or cipher size. For example, AES would have 16 bytes for IV. Besides, IV type can also be selected, i.e. eseqiv, seqiv, chainiv ...