final cog

Sorry for the delay, I had more to learn about Apache's proxypass directive.

See http://www.finalcog.com/recombinant-hashes for some details of, and applications for, the algorithm.

The demo is now running, the urls are:

• http://www.finalcog.com/hash
• http://www.finalcog.com/combine

To use the demo:

1. Open the two urls in two browser windows side-by-side.
2. Type some words (16 chars max) into the /hash page - it will then show your data in hex, and twelve hashes of your data.
3. Cut and paste any five (or more) hashes into the /combine page and click submit. It should recreate your original data from the hashes. Note: you have to paste the hashes into their correct boxes.

This demo deals with data on a tiny scale, just to get the principles across. Real data would typically be handled as 4Kb chunks, with many 512 byte hashes made (and distributed) from each 4Kb chunk. Any 9 hashes could be used to recreate an original 4Kb chunk.

I have performance tested the algorithm on a (single-core) Pentium M 1.6GHz, it can combine hashes at the rate of 5-6Mbit/s at 100% CPU load. I have no reason to believe that performance won't scale linearly with CPU speed. Also, the algorithm is embarrassingly parallel.