Microsoft Download Center Archive

AES-CBC + Elephant diffuser

  • Published:
  • Version: 2006-08
  • Category: Document
  • Language: English

The specifications of the AES-CBC + diffuser algorithm used in BitLocker Drive Encryption

  • The Bitlocker Drive Encryption feature of Windows Vista poses an interesting set of security and performance requirements on the encryption algorithm used for the disk data. We discuss why no existing cipher satisfies the requirements of this application and document our solution which consists of using AES in CBC mode with a dedicated diffuser to improve the security against manipulation attacks.


Status: Live

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FileSHA1 HashSize
BitLockerCipher200608.pdf50d4f6fc79bf34043cda1265b915fc96e56eb5a2161 KB

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System Requirements

Operating Systems: Windows 10, Windows 7 Professional, Windows 8 Pro, Windows 8.1, Windows Vista

  • BitLocker is only availble in the Enterprise and Ultimate editions of Windows Vista

Installation Instructions

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