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Date: Thu, 3 Oct 2013 07:35:32 -0600
Message-ID: <CADjHg8GDqAFsmO-yNSPpgcvm4uRfwz4z7u-gm8Ur7ScuB=6joA@mail.gmail.com>
From: Daniel Lidstrom <lidstrom83@gmail.com>
To: Bitcoin Dev <bitcoin-development@lists.sourceforge.net>
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Subject: Re: [Bitcoin-development] Identity protocol observation
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A couple more thoughts on this:

1) Both c and k can be kept if c is pronounced 'ch', giving ~10.9 bits per
phoneme.
2) An extra phoneme (4 encode 43 bits total) gives room to put extra
information into the name, e.g. the first 5 bits could be input as the key
to a PRP that permutes the last 38 back to a standard encoding of a tx
location.  This would give the user 32 random names per sacrifice to choose
from, and 38 bits to encode its location in the blockchain, which is enough
for pretty large blocks.

Sample 4 phoneme names:
~milmoz-vyrnyx
~mypnoz-fojzas
~sawfex-bovlec
~fidhut-guvgis
~bobfej-jessuk
~furcos-diwhuw
~wokryx-wilrox
~bygbyl-caggos
~vewcyv-jyjsal
~daxsaf-cywkul

They're not that bad IMHO, especially if you get to pick a decent one from
a bunch.


On Thu, Oct 3, 2013 at 3:35 AM, Daniel Lidstrom <lidstrom83@gmail.com>wrote:

> The location of a tx in the blockchain can be encoded in n=log2(h)+log2(t)
> bits, where h is the block height, and t is the number of transactions in
> the block.  Currently h~250,000 and t~500, so n~27.  A CVC phoneme encodes
> ~10.7 bits *, so a transaction today can be located in the blockchain with
> 3 of these, e.g. reb-mizvig.  This is reasonably short, readable and
> memorable.
>
> The identity protocol Jeff Garzik is working on will link a public key
> fingerprint to a miner sacrifice transaction.  This tx could in turn be
> uniquely described with a short name as above.  Associating this name with
> the public key becomes secure once the tx is sufficiently buried in the
> blockchain.  In the identity protocol, lightweight clients check the
> validity of a sacrifice tx by checking that its merkle path is valid.  But
> this path encodes, via the ordering of the hashes at each level, the
> location of the transaction in the block, so the lightweight client can
> verify the sacrifice tx's short name using only the information he already
> has.
>
> Some more random names:
> vec-halhic
> wom-vizpyd
> guv-zussof
> jog-copwug
> seg-rizges
> jyg-somgod
> pax-synjem
> zyg-zuxdyj
> gid-mutdyj
> rel-hyrdaj
>
> Sources of inspiration:
> urbit.org
> https://en.bitcoin.it/wiki/Identity_protocol_v1
>
> * This is somewhat restricted: I disallowed q for obvious reasons and k
> because it conflicts with c, and c looks much softer and less like
> Klingon.  H is allowed for the first consonant, but not the second, and x
> is allowed for the last one, but not the first one.  Y is a vowel, but not
> a consonant.  Maybe these weren't quite the right choices.  Paint away!
>

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<div dir=3D"ltr"><div>A couple more thoughts on this:<br><br></div><div>1) =
Both c and k can be kept if c is pronounced &#39;ch&#39;, giving ~10.9 bits=
 per phoneme.<br></div><div>2) An extra phoneme (4 encode 43 bits total) gi=
ves room to put extra information into the name, e.g. the first 5 bits coul=
d be input as the key to a PRP that permutes the last 38 back to a standard=
 encoding of a tx location.=A0 This would give the user 32 random names per=
 sacrifice to choose from, and 38 bits to encode its location in the blockc=
hain, which is enough for pretty large blocks.<br>
<br></div><div>Sample 4 phoneme names:<br>~milmoz-vyrnyx<br>~mypnoz-fojzas<=
br>~sawfex-bovlec<br>~fidhut-guvgis<br>~bobfej-jessuk<br>~furcos-diwhuw<br>=
~wokryx-wilrox<br>~bygbyl-caggos<br>~vewcyv-jyjsal<br>~daxsaf-cywkul<br>
<br></div><div>They&#39;re not that bad IMHO, especially if you get to pick=
 a decent one from a bunch.<br></div></div><div class=3D"gmail_extra"><br><=
br><div class=3D"gmail_quote">On Thu, Oct 3, 2013 at 3:35 AM, Daniel Lidstr=
om <span dir=3D"ltr">&lt;<a href=3D"mailto:lidstrom83@gmail.com" target=3D"=
_blank">lidstrom83@gmail.com</a>&gt;</span> wrote:<br>
<blockquote class=3D"gmail_quote" style=3D"margin:0 0 0 .8ex;border-left:1p=
x #ccc solid;padding-left:1ex"><div dir=3D"ltr">The location of a tx in the=
 blockchain can be encoded in n=3Dlog2(h)+log2(t) bits, where h is the bloc=
k height, and t is the number of transactions in the block.=A0 Currently h~=
250,000 and t~500, so n~27.=A0 A CVC phoneme encodes ~10.7 bits *, so a tra=
nsaction today can be located in the blockchain with 3 of these, e.g. reb-m=
izvig.=A0 This is reasonably short, readable and memorable.<br>

<br>The identity protocol Jeff Garzik is working on will link a public key =
fingerprint to a miner sacrifice transaction.=A0 This tx could in turn be u=
niquely described with a short name as above.=A0 Associating this name with=
 the public key becomes secure once the tx is sufficiently buried in the bl=
ockchain.=A0 In the identity protocol, lightweight clients check the validi=
ty of a sacrifice tx by checking that its merkle path is valid.=A0 But this=
 path encodes, via the ordering of the hashes at each level, the location o=
f the transaction in the block, so the lightweight client can verify the sa=
crifice tx&#39;s short name using only the information he already has.<br>

<br>Some more random names:<br>vec-halhic<br>wom-vizpyd<br>guv-zussof<br>jo=
g-copwug<br>seg-rizges<br>jyg-somgod<br>pax-synjem<br>zyg-zuxdyj<br>gid-mut=
dyj<br>rel-hyrdaj<br><br>Sources of inspiration:<br><a href=3D"http://urbit=
.org" target=3D"_blank">urbit.org</a><br>

<a href=3D"https://en.bitcoin.it/wiki/Identity_protocol_v1" target=3D"_blan=
k">https://en.bitcoin.it/wiki/Identity_protocol_v1</a><br><br>* This is som=
ewhat restricted: I disallowed q for obvious reasons and k because it confl=
icts with c, and c looks much softer and less like Klingon.=A0 H is allowed=
 for the first consonant, but not the second, and x is allowed for the last=
 one, but not the first one.=A0 Y is a vowel, but not a consonant.=A0 Maybe=
 these weren&#39;t quite the right choices.=A0 Paint away!<br>

</div>
</blockquote></div><br></div>

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