Once I made the leap from 'digest' to 'hash', my searching has been more effective, and I finally turned up (one of) the references I read previously that leads to my concerns regarding the truncation of a larger digest algorithm.

In particular, see the section headed "Funneling" and the paragraph that reads "For example, consider XORhash and 30-byte keys. All 30 lowest-order key bits funnel into only the lowest-order bit of the internal state. Every set of a billion (2^30) keys, which differ only in the lowest order key bits, maps into just 2 hash values, even though 101 hash values are available."

Another reference that I haven't yet tracked down, but may be linked indirectly from the above, suggested that testing had shown that truncation (of any form) of MD5 resulted in poor distribution. I don't have the knowledge to either challenge or verify that assertion.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.
"Too many [] have been sedated by an oppressive environment of political correctness and risk aversion."

In reply to Re^6: 64-bit digest algorithms by BrowserUk
in thread 64-bit digest algorithms by BrowserUk

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