In the blog on the "Semantic Web for Navy Information Dominance Operations" I estimated that with sensors included the Navy could be generating over 300 petabytes of information per day.* Most of this data would come from sources (such as UAVs) that have limited use for only a few hours. Therefore, the accumulation of data for forensic purposes could initially add further storage requirements for not much more than >1,000 petabytes.
The idea of ultimately requiring thousands of petabytes to support the Navy's Information Dominance objectives has raised the question about affordability.
The current costs of a petabyte range from the stripped down $117,000/petabyte from Backblaze (http://blog.backblaze.com/2009/09/01/petabytes-on-a-budget-how-to-build-cheap-cloud-storage/) to the $826,000/petabyte price from Dell. Considering the scale and software available within the Navy Private Cloud, we will use Backblaze as the basis for estimating the affordability of gigantic disk files.
The 2010 cost of 300 petabytes is $35 millions, or 12 cents per gigabyte. This is much less than the total costs of the legacy disk files that are in place for thousands of Navy servers. Huge savings are therefore available immediately.
The cost of disks is declining faster, at 25-30% per year, than the costs of semiconductor memories that follow Moore's Law. A conservative estimate for 2020 would therefore deliver to the Navy a petabyte for about $6,500. The daily 300 petabytes could be then supported for a highly cost effective $2 million.
Cloud computing offers enormous cost savings in disk storage immediately and in the future.
None of this includes the costs of software to operate petabyte files in the cloud. None of this includes the costs of redundancy and backup. However, the projected costs are well within the limits of the Navy’s IT spending. Planning for the migration to cloud computing can therefore proceed without concerns about the size of data files. The size of the Information Dominance files should also not be seen as a deterrent to proceeding with the virtualization of data files without further delay.