[freenet-devl] Looking for a research project?

[Brian G. Powell]

Timm Murray writes:
 > I'm CCing this to the Beowulf mailing list, as there are people there who
 > will know a lot more about this then me.
 > 
 > For the benifit of the Beowulf people:  On the Freenet mailing list (see
 > www.freenetproject.org if you're unfamiler with Freenet), we're talking
 > about doing a research project involving Freenet, particularly doing
 > simulations of the network.
 > 
 > ----- Original Message -----
 > From: "Ian Clarke" <ian at hawk.freenetproject.org>
 > To: <devl at freenetproject.org>
 > Sent: Monday, April 16, 2001 12:58 PM
 > Subject: Re: [freenet-devl] Looking for a research project?
 > 
 > >On Mon, Apr 16, 2001 at 02:21:32PM -0700, Timm Murray wrote:
 > >> Anyone else around here an armchair Chaos Theorist (or even a real Chaos
 > >> Theorist)?  If the simulations don't incorperate the size-bias they will
 > be
 > >> fately flawed.
 > >
 > >It depends what you are using the simulations for.  We have primarily
 > >used them to test the scalability of the general system, I don't think
 > >the size bias would affect this, it will really effect document's
 > >longevity in the system, which we haven't measured yet.
 > >
 > >> Freenet is a natural system, and thus any simuations are
 > >> susceptable to the Butterfly Effect.
 > >
 > >Not all complex systems are chaotic.  I disagree that Freenet is a
 > >chaotic system since it doesn't seem to be particularly reliant on the
 > >initial configuration of the network (a chaotic system would be).

*The above statement is correct; however, "Freenet" or a system like it
may behave in ways that are chaotic, in the engineering and mathematical
sense of the word "chaotic".

**Investigations into whether it is or not might be interesting; but, they
would be interesting to FREENET users that might wonder about network load
and dynamic changes and what may be most important: predictability.

*Very few nonlinear dynamic systems exhibit "chaos"; some estimates are around
2% of such systems.

**Three elements are required:

1) Horseshoe effect is present (like a Cantor Set).

2) Sensitivity on initial conditions: Will a tiny change in the initial
parameters in the initial phase of the creation or execution of the system
result in wildly varying results.

3) Unpredictability: Given any known set of variables, when measured at any
known time, can we accurately predict a later set of values when measured
simultaneously (e.g. the Butterfly Effect comes to mind well for this
attribute especially).



 > >
 > >> Freenet is a natural system, and thus any simuations are
 > >> susceptable to the Butterfly Effect.
 > >
 > >Not all complex systems are chaotic.  I disagree that Freenet is a
 > >chaotic system since it doesn't seem to be particularly reliant on the
 > >initial configuration of the network (a chaotic system would be).
 > 
 > I would argue that the initial configuration of the /network/ isn't chaotic,
 > but the path a document takes upon initial insertion and the subsequent
 > requests are.  You were right to say that it depends on what part of Freenet
 > you're simulating.
 > 
 > I think the best simulation you could have would be a Beowulf cluster with
 > each node in the cluster running multiple Freenet nodes (all on a diffrent
 > port and data store).  If Fred (for the Beowulf people: Fred is the Freenet
 > Refrance program, which is written in Java) can someday work well with a GCJ
 > compile, you could put something like 20 Freenet nodes on a single Beowulf
 > node, even with each node being only a 486.  Note that our little
 > Freenet-in-Beowulf never talks to the Freenet on the Internet itself.
 > 

In any case, thanks for the thread.  Its very interesting, if some research
is done on this, please give us some of the results.

;-)

...
 > 
 > Timm Murray
 > --------------------
 > 
 > Life is like a perl script:  Really short and messy.
 > 
 > 
 > 
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