Storing Archival Data - Part Deux: Page 2 of 5

The primary difference between archival data and active data
is that active data's contents are dynamic while an archive contains objects
like emails and documents that have fixed contents.  A user may edit and update a document for
weeks, saving multiple interim revisions to a primary NAS and each version will
replace the previous version -- once the file is archived each new version has to
be saved, cataloged and indexed.
This nature of archival data means the storage device that
holds it should be designed to store multiple versions of files. While this function can be implemented in the
archiving software, having a storage system whose file system can store and
track multiple versions expands the range of data movers you can choose from to
include HSM or ILM tools not explicitly designed for archiving.
Retention enforcement on the other hand has to be a function
of the storage device. In fact, retention
enforcement was the raison d'etre for both the use of magneto-optical WORM
disks and the development of specialized storage systems for archival
data. Users shouldn't be allowed to
delete or modify files and emails in the archive to cover their tracks when the
boss is looking to find out who caused us to lose the Johnson account.