Patent ID: 8266430

Claim:
A system for shredding a target file, comprising: a processor configured to: receive a first directory manager key; decrypt a directory manager file using the first directory manager file key, wherein the directory manager file includes an encryption key that is used when reconstructing a target file, wherein the target file is stored as one or more segments in a storage system that deduplicates stored segments, wherein the one or more segments are stored in a plurality of tiers in a hierarchical data structure, wherein a segment encryption key for one of the one or more segments in a lower tier is stored as an encrypted data in a segment in a next higher tier, and wherein the one or more segments are stored in containers, wherein each container includes one or more data segments and metadata; modify the directory manager file by deleting a reference to the target file, wherein the reference includes the encryption key, and wherein the deletion of the reference to the target file in the directory manager file shreds the target file, wherein shredding the target file makes retrieving the target file impractical; receive a second directory manager key; and encrypt the modified directory manager file using the second directory manager file key, wherein the encrypted modified directory manager file is stored in a hierarchical data structure; and a memory coupled to the processor and configured to provide the processor with instructions.