> 2. Fixity trade offs decision tool. Given different systems, different
> kinds of content, different scales of content etc. there should be
> different approaches to the frequency of fixity checking. There is interest
> in developing some kind of grid, or decision tree that could help orgs
> decide the best approach to how frequently to check the fixity of their
> content.
>
It seems to me that 2 is the logical foundation for 1. That is -- one
should have a desired strategy for fixity checking in mind before
developing guidance aimed at helping those new to the area to implement
such a strtagey.
> Anyone interested in number 1 specifically or number 2? Should we start
> on both and see how it breaks out?
> For number 2 were a number of ways we could break this out and look at it,
> or rather a number of parameters to frame it. Here are the ones listed
> above:
>
> System type
> Type of content
> Scale of content (not sure what this means)
> Frequency based on those factors
> Any others?
>
(I'm not sure what is meant by "system type". )
My hypothesis is that the factors that drive an appropriate choice of
strategies are:
- number of objects in collections
- number of collections
- size of objects
- willingness to accept risk of loss ( or alternatively, budget --
which will indirectly bound risk acceptance)
- content type / structure
- trust model
Based on these factors the strategy at the "leaf" nodes of the tree might
involve recommended combinations of parameters :
- compression algorithm, number of replication, fixity computation
algorithm, verification algorithm, verification frequency, repair frequency
best,
Micah
Karen
>
>
>
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--
------------------------------------------------------------------------------------------------------------------------------
Micah Altman, Ph.D. <http://micahaltman.com> Twitter: @drmaltman
Director of Research -- MIT Libraries; Head/Scientist, Program on
Information Science
Non-Resident Senior Fellow, Brookings Institution
"Entia non sunt multiplicanda sine necessitate" - Doctor Invincibilis
(Corollary, "Ad indicia spectate.")
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