The problem that an IV tries to remedy is that many messages have a more or less fixed format for the start of the message, so you have some plaintext. This is one of the reasons why some many German Enigma messages were broken.
The problem that an IV tries to remedy is that many messages have a more or less fixed format for the start of the message, so you have some plaintext. This is one of the reasons why some many German Enigma messages were broken.