original: Background DES uses a 56 - bit key, meaning that there are 256 possible keys under which a message can be encrypted.
simplifications: Under Background DES there are 256 possible keys by which a message can be encrypted. Background DES uses a 56 - bit key that 256 possible keys are under, which messages can be encrypted. Background: DES uses a 56 - bit key. This means that there are 256 possible keys for encrypting a message. DES uses a 56 bit key.  This means it is possible for a message can be encrypted under 256 keys. Background DES uses a 56 - bit key. That means there are 256 possible keys under which a message can be encrypted. Background DES uses a 56-bit key which means a message can be encoded under 256 possible keys. Background DES uses a 56 - bit key. This means that there are 256 possible keys under which a message can be made secure. DES uses a 56-bit key. A 56-bit key means that there are 256 possible keys under which a message can be encrypted. Back ground DES uses a 56-bit key, which means there are 256 possible keys to encrypt a message. Background DES uses a 56 - bit key, meaning that there are 256 possible keys under which a message can be coded.