On Thu, 27 Aug 2009, Jimmy Ghaphery wrote:

> We have a historic idea of what it means to maintain space for analog 
> collections. For many institutions a lot of that initial funding has come 
> from capital building funds. While the technological solutions are not clear 
> to me at this point (and I'm benefiting from this thread on that), I am not 
> sure if this won't turn into more of a long-term business problem.
>
> Has anyone been able to give a projection to their management on what the 
> total cost per TB is for preservation over even a short horizon of 10 years?

I think it was the NSSDC (National Space Science Data Center) who had done 
some estimates, and I can't remember exactly what they were, I do remember 
that they had basically made the assumption that storage would continue to 
get cheaper and larger, and that computers to handle any verification and 
reformatting would get faster, resulting in the costs dropping off 
exponentially.

The result, if you were to convert to present dollars (to charge the group 
whose data you were taking), the cost of short term storage (~20 years?) 
was about the same as indefinate storage.

Unfortunately, I can't remember who it was (Tim Eastman?  Ed Grayzek? 
Joe King?  ... I don't think it was Don Sawyer) or where it was (Tim gave 
a talk at ASIS&T in 2006; almost all of 'em spoke at the Science Archives 
in the 21st Century workshop)

As I can't find the source of that, I don't know if this just came down to 
the technical aspects, or if it also included issues in understanding the 
data being preserved.  It's possible that they use the PDS cost analysis, 
which assumes that those costs are up-front:

 	http://pds.nasa.gov/tools/cost-analysis-tool.shtml

(Phases A-D are before the mission even launches; phase E is basically 
everything once data starts being collected)

...

And to look at some of the costs that you have to consider when archiving, 
see, from 1999 (so the numbers won't be right for today) :

 	How Many Terabytes Was That? Archiving and Serving Solar Space
 	Data Without Losing Your Shirt
 	http://umbra.nascom.nasa.gov/aas_spd/abstracts/aas199906.pdf

-Joe

ps.  I looked at the pricing for cloud storage, where we'd only be holding 
60TB at any one time, but adding 2TB per day, and the prices were insane 
before we even estimated people downloading the data.