Hi everyone, I recently ran into a paper on convergent encryption, which is a way of encrypting file blocks by their hashes. The hashes (keys) are stored with the blocks, encrypted with the public key of any authorized readers. This allows a server to pool identical files, as they end up having identical encrypted blocks. This would allow BackupPC to still work as it does now. Naturally, file size, location, quantity, etc are visible but the contents wouldn't be.
I'm not sure if this has been suggested before, but a brief peruse of the archives didn't turn anything up. It seems like the arguments against encryption in the past found the pooling issue insurmountable. I appended bibtex for the paper below. Cody @INPROCEEDINGS{Douceur02Reclaimingspacefrom, author = {J.~R. Douceur and A. Adya and W.~J. Bolosky and P. Simon and M. Theimer}, title = {Reclaiming space from duplicate files in a serverless distributed file system}, booktitle = {ICDCS '02: Proc. 22nd International Conference on Distributed Computing Systems}, year = {2002}, pages = {617--624}, month = {2--5 July }, abstract = {The Farsite distributed file system provides availability by replicating each file onto multiple desktop computers. Since this replication consumes significant storage space, it is important to reclaim used space where possible. Measurement of over 500 desktop file systems shows that nearly half of all consumed space is occupied by duplicate files. We present a mechanism to reclaim space from this incidental duplication to make it available for controlled file replication. Our mechanism includes: (1) convergent encryption, which enables duplicate files to be coalesced into the space of a single file, even if the files are encrypted with different users' keys; and (2) SALAD, a Self-Arranging Lossy Associative Database for aggregating file content and location information in a decentralized, scalable, fault-tolerant manner. Large-scale simulation experiments show that the duplicate-file coalescing system is scalable, highly effective, and fault-tolerant.}, doi = {10.1109/ICDCS.2002.1022312}, url = {http://ieeexplore.ieee.org/xpls/abs_all.jsp?arnumber=1022312} } ------------------------------------------------------------------------------ The NEW KODAK i700 Series Scanners deliver under ANY circumstances! Your production scanning environment may not be a perfect world - but thanks to Kodak, there's a perfect scanner to get the job done! With the NEW KODAK i700 Series Scanner you'll get full speed at 300 dpi even with all image processing features enabled. http://p.sf.net/sfu/kodak-com _______________________________________________ BackupPC-users mailing list BackupPC-users@lists.sourceforge.net List: https://lists.sourceforge.net/lists/listinfo/backuppc-users Wiki: http://backuppc.wiki.sourceforge.net Project: http://backuppc.sourceforge.net/