Archived posting to the Leica Users Group, 2012/08/22
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]They probably keep redundant copies across multiple tapes and new copies being refreshed every X year cycle (with X probably at least for 10 years). On Wed, Aug 22, 2012 at 1:03 PM, Spencer Cheng <spencer at aotera.org> wrote: > Hi Adam, > > According to the National Archive in Canada, the only archival medium > suitable for 100 years is acid-free paper or microfiche. Our national > census data which has to be stored for 75 years by law is delivered to the > Archive on paper as far as I know. > > My preference is for laser-etched granite tablets. ;-) > > Modern tape drives have their own ECC scheme when they write data. Amazon > would have to constantly copy the data in order to ensure that any of the > tapes hasn't gone bad. Modern tapes are much improved over the DAT drives I > used 15 years ago but they certainly are not archival quality. > > Keeping any system up for 99.999% time is a major struggle requiring very > complex engineering. My imagination is significantly stretched by > 99.99999999%. It definitely sounds like marketing speak. :) > > Regards, > Spencer > > On Aug 22, 2012, at 15:16, Adam Bridge <abridge at mac.com> wrote: > > > You shouldn't really be surprised, Spencer. If data redundancy is built > into the storage - lots of extra bits to allow for recoverable data - then > you'd get the durability that Amazon quotes. > > > > You're guessing that they store on tape. That might be true but for > long-term storage tape isn't an ideal candidate. However it's stored, > Amazon says they have a technology, or a growth path for technology, that > will keep your data alive and available for the indefinite future. > > > > Looks pretty attractive to me. > > > > Adam > > > > On Aug 21, 2012, at 6:12 PM, Spencer Cheng <spencer at aotera.org> wrote: > > > >> Sounds nice. Sounds a bit too good to be true. I would guess Amazon > stores the data on tape on multiple sites. > >> > >> "Amazon Glacier is designed to provide average annual durability of > 99.999999999% for an archive" > >> > >> I am surprised that that level of durability is possible on perishable > media (and I don't really believe it :). > >> > >> One aspect of archival storage of digital data which is often > overlooked is that digital data has to be regularly transcribed/converted > to a current format for the archive to be useful. > >> > >> Regards, > >> Spencer > >> > >> On Aug 21, 2012, at 18:28, Adam Bridge <abridge at mac.com> wrote: > >> > >>> Amazon has announced "Glacier" as a long-term storage / infrequent > retrieval service. It would seem perfect for those who wish to have a > completely separate backup for their important image libraries. > >>> > >>> You can read about it here: > >>> > >>> <http://aws.amazon.com/glacier/> > >>> > >>> This is NOT for ready on-line storage. You might have to wait 5 hours > to get your data. But it looks reasonably affordable. > >>> > >>> Adam Bridge > >>> > >>> > >>> _______________________________________________ > >>> Leica Users Group. > >>> See http://leica-users.org/mailman/listinfo/lug for more information > >>> > >> > >> > >> _______________________________________________ > >> Leica Users Group. > >> See http://leica-users.org/mailman/listinfo/lug for more information > > > > > > _______________________________________________ > > Leica Users Group. > > See http://leica-users.org/mailman/listinfo/lug for more information > > > > > _______________________________________________ > Leica Users Group. > See http://leica-users.org/mailman/listinfo/lug for more information > -- // richard <http://www.richardmanphoto.com>