For a long time there have been a number of possible "holy grails" for digital preservation, ideas that if it were possible to implement them would transform the problem. One of them has been the idea of an Internet-scale peer-to-peer network that would use excess disk storage at everyone's computers, in the same way that networks like
Folding@Home use excess CPU, to deliver a robust, attack-resistant, decentralized storage infrastructure.
Intermemory, from NEC's Princeton lab in 1998, was one of the first, but the concept is so attractive that there have been many others, such as Berkeley's
Oceanstore. None have succeeded in attracting the mass participation of projects such as Folding@Home. None have become a widely-used infrastructure for digital preservation because without mass participation none provides the needed robustness or capacity.
By far the most successful peer-to-peer network in attracting participation has been Bitcoin, because the reward for participation is monetary. Now, it seems to me that Andrew Miller and his co-authors from the University of Maryland and Microsoft Research have taken a giant step towards this "holy grail" with their paper
Permacoin: Repurposing Bitcoin Work for Data Preservation (hereafter MJSPK). This is despite the fact that, as I predicted in a
comment last April, the current Bitcoin implementation has now
definitively failed in its goal of establishing a decentralized currency because GHash has, for extended periods,
controlled an absolute majority of the mining power. Follow me below the fold for my analysis of Permacoin and how this failure affects it.