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How secure is the SSMDF data file format?

SSMDF is very secure.  SSMDF places sequence numbers in each block header that are sequentially incremented for each record in a migration.  A break in the sequence signifies corruption of the data format.  As each new migration stream is started, this sequence number is reset to 1.  These headers also contain ?ǣcookies?ǥ which are used to ensure that the block header is well formed.  An incorrect value for this cookie signifies a data format corruption.  Other records (e.g file header) also contain sequence numbers which provide the same purpose as above. 

 

Hence, if a write is interrupted by a power failure (for example), the system can scan back through the records until the last good ?ǣEnd of File?ǥ record is found and recover from that point. 

 

Article ID: 10483 Article Created: 11-04-2013 14:29 PMLast Modified: 11-04-2013 14:29 PM

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