The Grapevine Project

Anthony Jones ajones@clear.net.nz
Mon, 10 Dec 2001 11:37:05 +0800


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On Monday 10 December 2001 04:02, Oskar Sandberg wrote:
> On Fri, Dec 07, 2001 at 12:16:15PM +0800, Anthony Jones wrote:
> <>
>
> > 1.
> > It is relatively well protected against trying to insert large amounts of
> > data in a certain area of keyspace.
> >
> > Large data is stored in the form of a Freenet style CHK that is you hash
> > the contents of your data and store it using that key.  Redirects from a
> > human readible text string are keyed from the hash of the text string.
> >
> > This means that you can't just pick an area of keyspace where you want to
> > insert the data.  Even if you can insert one file in a particular area of
> > keyspace you would need to insert a large number of files in a small area
> > of keyspace to run it out of disk space.
>
> The problem is that, even assuming perfect division of the keyspace
> between the nodes, the work for finding data that hashes into a nodes
> "range" using a rejection method is still of the order of the number of
> nodes in the network. Regardless of the size of the keyspace, you cannot
> assume that this will be unbreakable - even under the most optimistic
> growth models it is still << 2**32.

Oscar,

You're right.  If we've got a million nodes then it's only going to take a 
million guesses to get the node that you're trying to overload.  We're going 
to have to work out a defence for this.  Thank you for your help.

Anthony
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