The current state of anonymous file-sharing - Marc's Blog

a certain throughput/security tradeoff, it extremely extends the amount and availability
of files. Both, search queries and results are only forwarded between trusted peers. The
"official" implementation of turtle hopping, which was developed at the Vrije Universiteit
in Amsterdam also uses encryption between hops to keep eavesdroppers from listening
to the searches.
A great source of further information concerning the darknet pattern is "The Darknet
and the Future of Content Distribution" by Microsoft [9]
5.2 The Brightnet pattern
The word Brightnet makes one thing pretty clear: it’s the opposite of a Darknet. To
freshen up you memories: In the Darknet pattern, you only control WHO you share
your data with, but once you decide to share with a peer, you usually don’t have any
secrets from that node about WHAT you share.
In the Brightnet pattern it is exactly the opposite: you usually don’t care that much
about who you trade data with, but the data itself is a "secret".
This might seem a little bit confusing, how can data that is openly shared with everyone
be a secret?
To understand this, one has to look at the typical bits and bytes that are shared in a
file-sharing application: Usually, every piece of data does not only consists of arbitrary
numbers, but it has a certain meaning. It is part of the movie "xyz", the song "abc"
or the book "123". When uploading even a small portion of this data, you might be
infringing copyright or, depending where you live, might get yourself into all sorts of
trouble for the content you downloaded. This could lead to the situation that every
government agency or corporation could tell if you’re sharing/acquiring a file by either
simply receiving a request from or sending a request to you (given that you’re on an
"open" network) or looking at the transfered data on an ISP level.
The main idea behind the brightnet pattern is to strip the meaning from the data
you transfer. Without any distinct meaning, the data itself isn’t protected by any
copyright law or deemed questionable in any way. It would be totally fine to share
and download this meaningless data. To end up with "meaningless" data, the current
brightnet implementations use a method called "multi-use encoding" as described in the
paper "On copyrightable numbers with an application to the Gesetzklageproblem[19] by
"Cracker Jack" (The title is a play on Turing’s "On computable numbers").
The simplified idea is to rip apart two or more files and use an XOR algorithm to
recombine them to a new blob of binary data which, depending on the way you look at
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