[p2p-hackers] Generalizing BitTorrent..

[Adam Back]

What about rsync?  Perhaps you could just start from what a given peer
has, rsync that to n different peers.  Presuming the n peers have the
same starting point.

Gregory Smith wrote:
> -most- of the hashes of the fixed sized pieces are likely to change;
> certianly -way- more than 5% anyways.  why?  because the common data
> has shifted around or in the case of compressed streams of data
> (.tar.bz2) the entire stream will be different.  To get any benefit
> from this the content would need to be extreemly carefully packaged.
> no zips, no tars, no compression, etc.  That alone could destroy the
> benefit.

Yah so you should gzip / bzip the chunks on download, that way the
binary diff (rsync) gets to see the diffs.

btw you can think of rsync as an interactive compression algorithm
discovering and fetching the diffs between what the client has and
what the server has.

> updates that share data should be published as binary diffs against
> the previous version.  Downloading n+1 becomes a recursive "download
> n and the n->n+1 diff" operation.

btw What binary diff does the kernel distribution use?  I don't see a
binary diff package installed but maybe I'm missing it.

Are you talking about the source diffs?  (These are not binary).

Adam