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Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

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Tahoe Least Authority Filesystem / AllMyData.org

From: "andrew cooke" <andrew@...>

Date: Tue, 13 Jan 2009 01:58:38 -0300 (CLST)

This is a distributed, secure file system that uses an erasure code -
http://en.wikipedia.org/wiki/Erasure_code - and a capability access
control model - http://en.wikipedia.org/wiki/Capability-based_security

The idea is that a file is encrypted and split into fragments which are
distributed across many computers.  Only a fraction of those are needed to
reassemble the file (think RAID-5, but encrypted).

The file is identified using a URI that includes the rights (read/write)
to the data (this kind of approach always reminds me of fantasy novels
where knowing something's "true name" gives you power over it).  One
problem with that approach is that it's difficult to keep names secret -
see open issue at
http://allmydata.org/trac/tahoe/browser/docs/known_issues.txt

There's a page here that discusses possible uses for such a system -
http://allmydata.org/trac/tahoe/wiki/UseCases

The source and more info are available via via
http://allmydata.org/source/tahoe/trunk/docs/about.html and
http://allmydata.org/trac/tahoe/wiki/Doc - see papers
http://allmydata.org/~zooko/lafs.pdf and
http://allmydata.org/~warner/pycon-tahoe.html

Obviously(?) you need a gateway that provides access to the data and a
network for that gateway to work with.  If you don't want to build you own
then http://allmydata.com/ seems to be the commercial side of things - $10
a month for unlimited storage (screenshot here shows $5 -
http://www.killerstartups.com/Web-App-Tools/allmydata-com-online-storage-backup
)

Andrew

TiddlyWiki on Tahoe

From: "andrew cooke" <andrew@...>

Date: Tue, 13 Jan 2009 02:03:23 -0300 (CLST)

After all that I forgot to give the link that made me start looking at the
whole system - here's Tiddlywiki running on Tahoe.  This is a read-only
link, but you could also distribute the URI for the writable link and make
have a multi-user distributed one-page wiki :o)

http://testgrid.allmydata.org:3567/uri/URI:DIR2-RO:j74uhg25nwdpjpacl6rkat2yhm:kav7ijeft5h7r7rxdp5bgtlt3viv32yabqajkrdykozia5544jqa/wiki.html

(In practice there's no concurrent edit management in Tiddlywiki so it
would be a little frustrating at times...)

Zooko seems to be one of the main Tahoe devs (afaict that's his real name
- I started this wild-goose chase by googling for it after seeing a credit
in the Python docs!)

Andrew

OFF

From: "Francesco Pierfederici" <fpierfed@...>

Date: Tue, 13 Jan 2009 12:01:52 +0100

Hi Andrew,

Happy new year, first of all ;-)

Have you seen the OFF System? As far as I can tell it tries to do similar things

http://offsystem.sourceforge.net/

Cheers,
Francesco

OFF

From: "andrew cooke" <andrew@...>

Date: Tue, 13 Jan 2009 13:11:27 -0300 (CLST)

---------------------------- Original Message ----------------------------
From:    "Francesco Pierfederici" <fpierfed@...>
Date:    Tue, January 13, 2009 8:01 am
--------------------------------------------------------------------------

Hi Andrew,

Happy new year, first of all ;-)

Have you seen the OFF System? As far as I can tell it tries to do similar
things

http://offsystem.sourceforge.net/

Cheers,
Francesco

Re: OFF

From: "andrew cooke" <andrew@...>

Date: Tue, 13 Jan 2009 13:19:25 -0300 (CLST)

Hi,

It reminded me of something, but I don't think it was OFF (as far as I
know, I've not seen that before).  I guess there are more of these around?

There are some differences, I think - Tahoe seems to be aiming at
"reliable distributed store with capabilities" while OFF seems to be more
about deniability.  Maybe the former is more likely to make money?

Happy New Year to you too (+ Sylvia),
Andrew

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