...my plan was to make the hash so that, for example, if the first three octets of the IP match, then the first three chunks of the hash would match

That sounds like a nice goal, but one thing to be wary of is making brute force attacks too easy. If you publish a hash of only the first three octets of an IP address, that's a somewhat smaller range of numbers I have to plough through to guess what the original numbers are. I get an even bigger advantage if I check only the blocks that I know are registered to some organization and look first at blocks from English speaking countries, etc.

Just a thought.

In reply to Re^5: monastery mark-upedness (brute force) by kyle
in thread monastery mark-upedness by my_nihilist

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