Usage notes

Consider that Control Vector Translate represents the capability to translate, by definition, the limitations on the operations that a key can be used for, into a different set of limitations. The control vector is the heart of security against the misuse of keys that were defined for a specific purpose. The masks that control what the key can be translated into being able to do (the right and left masks) are themselves single-length (8-byte), and are encrypted with DES. Therefore, the protection against translating the key to have more power (or less power) than it did before are protected with single-DES. This reduces the security (somewhat) of a double-length DES key. You cannot decrypt the double-length key with this approach, or gain access to a key that you did not otherwise have the rights to use. But you can make a key which you already have access to, on a system you already have access to, more powerful than it was before if you can break single-DES.