公开(公告)号：AT549688T

公开(公告)日：2012-03-15

申请号：AT07727987

申请日：2007-04-11

Applicant: IBM

Inventor： MULLEN SHAWN ,  SHANKAR RAVI ,  CELIKKAN UFUK ,  CONKLIN WILLIAM

IPC: G06F21/24 ,  H04L9/00

Abstract: Mechanisms for providing an encrypted file system are provided. The mechanisms use a combination of encryption methodologies so as to reduce the amount of decryption and re-encryption that is necessary to a file in the Encrypted File System in the event that the file needs to be modified. The encryption methodologies are interleaved, or alternated, with regard to each block of plaintext. In one illustrative embodiment, Plaintext Block Chaining (PBC) and Cipher Block Chaining (CBC) encryption methodologies are alternated for encrypting a sequence of blocks of data. The encryption of a block of plaintext is dependent upon the plaintext or a cipher generated for the plaintext of a previous block of data in the sequence of blocks of data so that the encryption is more secure than known Electronic Code Book encryption methodologies.