[Author Prev][Author Next][Thread Prev][Thread Next][Author Index][Thread Index]

Re: [tor-dev] Mnemonic 80-bit phrases (proposal)



Hi Sai,

It looks like you've put a lot of thought into what would make a good hash-to-word system. However, you have a false assumption, that dictionary systems can simultaneously have all three properties of Zooko's Triangle. This is a popular idea, but unfortunately untrue.

Hashes are effectively random and so have maximum information density. Words do not have maximum information density, they have redundancy, which is why they are easier to remember and tell apart from each other than random strings. However, this comes at the cost of making the words longer. The more redundant information that you add in terms of constraints such as part of speech, the longer you will need to make the words (on average) so that they can contain this additional information. If you look at the 4 little words post you will notice that the phrases are about 5 characters longer than the IPv4 addresses. Of course you could make the claim that sometimes longer strings are easier to remember than shorter ones. There is an intuitive appeal to the idea that words are more memorable than hexadecimal strings (or base64 or whatever). That might be true sometimes for special cases, but there is no evidence that it is true generally or in this particular case.

On Tue, Feb 28, 2012 at 3:27 PM, Sai <tor@xxxxxxxxxx> wrote:
Hello all.

We've written up our proposal for mnemonic .onion URLs.

See https://docs.google.com/document/d/sT5CulCVl0X5JeOv4W_wC_A/edit?disco=AAAAAERhFsE
for details; please read the full intro for explanations and caveats,
as some are important.

tl;dr: It's a system that would have all three properties of being
secure, distributed, and human-meaningful… but would *not* also have
choice of name (though it has the required *canonicality* of names),
and has a somewhat absurdist definition of 'meaningful'. :-P

Please feel free to put comments there or on list.

Right now we're at the stage just before implementation; namely, we
haven't yet collated the necessary dictionaries, but we have a
reasonably good idea of how the system would work, including needed
constraints on the dictionaries. If you have suggestions or comments,
now is a good time to talk about them, so that if any of it affects
the dictionary collation step we don't waste work.

Thanks,
Sai
_______________________________________________
tor-dev mailing list
tor-dev@xxxxxxxxxxxxxxxxxxxx
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev

_______________________________________________
tor-dev mailing list
tor-dev@xxxxxxxxxxxxxxxxxxxx
https://lists.torproject.org/cgi-bin/mailman/listinfo/tor-dev