Patent ID: 7685171
Filing Date: 2010-03-23
Classification: G06F,Y10S

Abstract:
1. A method of performing restoration processing for a data segment comprising: receiving a list of tokens representing a first data state of said data segment, each of said tokens corresponding to a data portion of said data segment, wherein information for a backup data set includes said list of tokens, a globally unique identifier uniquely identifying the backup data set from other backup data sets, and a digital signature in accordance with said list of tokens and said globally unique identifier; performing validation processing using said digital signature and said globally unique identifier to determine whether the information for the backup data set has been compromised, wherein said list of tokens is not used in subsequent processing steps for data restoration if said validation processing determines that the information has been compromised; scanning data portions of said data segment and determining a token for each data portion of said data segment, said token representing data currently stored in said data segment at said each data portion; for each data portion of said data segment, determining whether a first token from said list associated with said each data portion is different from a second token associated with said each data portion, wherein said second token is determined as part of said scanning and corresponds to data currently stored at said each data portion; and restoring each data portion of said data segment determined to have a first token that is different from a second token representing data currently stored at said each data portion, wherein said restoring said each data portion includes sending to a restoration server said first token for said each portion which is determined to be different from said second token for said each portion, and returning from the restoration server a copy of said each data portion corresponding to said first token, said copy representing said each data portion in said first data state.