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+To: Dave Scotese <dscotese@litmocracy.com>,

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+Thread-Topic: [bitcoin-discuss] Proposal to replace full blockchain with

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+Subject: Re: [bitcoin-dev] [bitcoin-discuss] Proposal to replace full

+ blockchain with recent history plus UTXO Set

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+--_000_PS2P216MB01795F6E52A18C73E20E9D5A9D160PS2P216MB0179KORP_

+Content-Type: text/plain; charset="us-ascii"

+Content-Transfer-Encoding: quoted-printable

+

+A fairly decent rework would be needed but it seems that the idea has merit=

+ initially.

+

+

+As it is now, it is not only that a utxo exists but, that the transaction i=

+t references and the block it is within can also be fully validated.

+

+

+So, if a utxo block set type existed then by consensus every so often a bun=

+ch of blocks containing just the validated utxo set to a given height, say =

+100,000 blocks below the current blockheight, and necessary header data cou=

+ld be appended onto the valid chain and nodes would be free to drop all pre=

+ceding blocks. I suspect that many wouldn't and that even many new nodes wo=

+uld still desire to download the full blockchain but, for the use case you =

+mention it would make sense.

+

+

+If done [right/wrong] it may even make Satoshi's fortune spendable. Somethi=

+ng to watch out for.

+

+________________________________

+From: bitcoin-discuss-bounces@lists.linuxfoundation.org <bitcoin-discuss-bo=

+unces@lists.linuxfoundation.org> on behalf of Dave Scotese via bitcoin-disc=

+uss <bitcoin-discuss@lists.linuxfoundation.org>

+Sent: Wednesday, 26 September 2018 1:46:54 AM

+To: Bitcoin Discuss

+Subject: Re: [bitcoin-discuss] Proposal to replace full blockchain with rec=

+ent history plus UTXO Set

+

+The image at imgur and the pastebin both reference block 542324 but the cor=

+rect block is 542322. As the pastebin shows, the decimal and hex represent=

+ations I gave for the block height did not match, and this is why. If you =

+use the Merkle root for block 542322 instead of 542324, you'll be able to s=

+ee the correct Game of Life play out and make the apron image.

+

+Dave.

+

+On Sun, Sep 23, 2018 at 11:38 AM Dave Scotese <dscotese@litmocracy.com<mail=

+to:dscotese@litmocracy.com>> wrote:

+I thought I didn't have access to the dev list and so intended to post the =

+following proposal to this discussion list, but used the wrong email addres=

+s. Anyway, my email did get into the dev list (https://lists.linuxfoundati=

+on.org/pipermail/bitcoin-dev/2018-September/016420.html) but I'll repeat it=

+ here:

+

+I've been working on an idea that relieves full nodes of storing the entire=

+ blockchain. Open source software generally relies on the fact that "enough=

+" people agree that it's secure. Bitcoin software works that way too. So if=

+ you understand enough to see that a UTXO set is valid at a certain block h=

+eight, and there are enough other people who agree and that set is recogniz=

+able by humans, then we can use that UTXO set and ditch the blockchain that=

+ existed up to that point. It would save a lot of storage and make it a lot=

+ easier to run a full node.

+

+Have you reviewed the source code from which your wallets were compiled? At=

+ some point, we all trust third parties, but generally (at least among peop=

+le who understand Bitcoin) they are large composite groups so that no small=

+ group or individual can profit from cheating.

+

+I look forward to answering any concerns and also to any offers of help. =

+I used block 542324 of the Bitcoin blockchain to make a memorable experienc=

+e using the game of life. I wrote a script for the open-source Game-of-Life=

+ software Golly and shared it in the paste at https://pastebin.com/k5Ssc0qk=

+. It produces the image at https://imgur.com/a/rwIQuVz. If someone can tell=

+ me how to get a UTXO Set from the bitcoin client, I'll send them $50 of bi=

+tcoin. Then I could get the SHA256 hash of that set and try to make a recog=

+nizable checkpoint for the Bitcoin blockchain. If someone runs Golly and sh=

+ares a video of the game playing out (into the apron-shaped image), I'll se=

+nd them $50 of bitcoin too.

+

+In a few decades when the blockchain has grown to a few terabytes and the U=

+TXO Set is still just a few gigabytes, I'd like to see more people start ru=

+nning full nodes without the hassle of a long wait and loads of storage spa=

+ce. That's what stops me from running one.

+

+

+--

+I like to provide some work at no charge to prove my value. Do you need a t=

+echie?

+I own Litmocracy<http://www.litmocracy.com> and Meme Racing<http://www.meme=

+racing.net> (in alpha).

+I'm the webmaster for The Voluntaryist<http://www.voluntaryist.com> which n=

+ow accepts Bitcoin.

+I also code for The Dollar Vigilante<http://dollarvigilante.com/>.

+"He ought to find it more profitable to play by the rules" - Satoshi Nakamo=

+to

+

+--_000_PS2P216MB01795F6E52A18C73E20E9D5A9D160PS2P216MB0179KORP_

+Content-Type: text/html; charset="us-ascii"

+Content-Transfer-Encoding: quoted-printable

+

+<html>

+<head>

+<meta http-equiv=3D"Content-Type" content=3D"text/html; charset=3Dus-ascii"=

+>

+<style type=3D"text/css" style=3D"display:none;"><!-- P {margin-top:0;margi=

+n-bottom:0;} --></style>

+</head>

+<body dir=3D"ltr">

+<div id=3D"divtagdefaultwrapper" style=3D"font-size:12pt;color:#000000;font=

+-family:Calibri,Helvetica,sans-serif;" dir=3D"ltr">

+<p style=3D"margin-top:0;margin-bottom:0">A fairly decent rework would be n=

+eeded but it seems that the idea has merit initially.</p>

+<p style=3D"margin-top:0;margin-bottom:0"><br>

+</p>

+<p style=3D"margin-top:0;margin-bottom:0">As it is now, it is not only that=

+ a utxo exists but, that the transaction it references and the block it is =

+within can also be fully validated.</p>

+<p style=3D"margin-top:0;margin-bottom:0"><br>

+</p>

+<p style=3D"margin-top:0;margin-bottom:0">So, if a utxo block set type exis=

+ted then by consensus every so often a bunch of blocks containing just the =

+validated utxo set to a given height, say 100,000 blocks below the current =

+blockheight, and necessary header

+ data could be appended onto the valid chain and nodes would be free to dro=

+p all preceding blocks. I suspect that many wouldn't and that even many new=

+ nodes would still desire to download the full blockchain but, for the use =

+case you mention it would make sense.</p>

+<p style=3D"margin-top:0;margin-bottom:0"><br>

+</p>

+<p style=3D"margin-top:0;margin-bottom:0">If done [right/wrong] it may even=

+ make Satoshi's fortune spendable. Something to watch out for.<br>

+</p>

+</div>

+<hr style=3D"display:inline-block;width:98%" tabindex=3D"-1">

+<div id=3D"divRplyFwdMsg" dir=3D"ltr"><font face=3D"Calibri, sans-serif" st=

+yle=3D"font-size:11pt" color=3D"#000000"><b>From:</b> bitcoin-discuss-bounc=

+es@lists.linuxfoundation.org &lt;bitcoin-discuss-bounces@lists.linuxfoundat=

+ion.org&gt; on behalf of Dave Scotese via bitcoin-discuss

+ &lt;bitcoin-discuss@lists.linuxfoundation.org&gt;<br>

+<b>Sent:</b> Wednesday, 26 September 2018 1:46:54 AM<br>

+<b>To:</b> Bitcoin Discuss<br>

+<b>Subject:</b> Re: [bitcoin-discuss] Proposal to replace full blockchain w=

+ith recent history plus UTXO Set</font>

+<div>&nbsp;</div>

+</div>

+<meta content=3D"text/html; charset=3Dutf-8">

+<div>

+<div dir=3D"ltr">

+<div>The image at imgur and the pastebin both reference block 542324 but th=

+e correct block is 542322.&nbsp; As the pastebin shows, the decimal and hex=

+ representations I gave for the block height did not match, and this is why=

+.&nbsp; If you use the Merkle root for block

+ 542322 instead of 542324, you'll be able to see the correct Game of Life p=

+lay out and make the apron image.<br>

+</div>

+<div><br>

+</div>

+<div>Dave.<br>

+</div>

+</div>

+<br>

+<div class=3D"x_gmail_quote">

+<div dir=3D"ltr">On Sun, Sep 23, 2018 at 11:38 AM Dave Scotese &lt;<a href=

+=3D"mailto:dscotese@litmocracy.com">dscotese@litmocracy.com</a>&gt; wrote:<=

+br>

+</div>

+<blockquote class=3D"x_gmail_quote" style=3D"margin:0 0 0 .8ex; border-left=

+:1px #ccc solid; padding-left:1ex">

+<div dir=3D"ltr">

+<div dir=3D"ltr">

+<div dir=3D"ltr">I thought I didn't have access to the dev list and so inte=

+nded to post the following proposal to this discussion list, but used the w=

+rong email address.&nbsp; Anyway, my email did get into the dev list (<a hr=

+ef=3D"https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2018-Septembe=

+r/016420.html" target=3D"_blank">https://lists.linuxfoundation.org/pipermai=

+l/bitcoin-dev/2018-September/016420.html</a>)

+ but I'll repeat it here:</div>

+<div dir=3D"ltr"><br>

+</div>

+<div dir=3D"ltr">I've been working on an idea that relieves full nodes of s=

+toring the entire blockchain. Open source software generally relies on the =

+fact that &quot;enough&quot; people agree that it's secure. Bitcoin softwar=

+e works that way too. So if you understand enough

+ to see that a UTXO set is valid at a certain block height, and there are e=

+nough other people who agree and that set is recognizable by humans, then w=

+e can use that UTXO set and ditch the blockchain that existed up to that po=

+int. It would save a lot of storage

+ and make it a lot easier to run a full node.<br>

+<br>

+Have you reviewed the source code from which your wallets were compiled? At=

+ some point, we all trust third parties, but generally (at least among peop=

+le who understand Bitcoin) they are large composite groups so that no small=

+ group or individual can profit

+ from cheating.<br>

+<br>

+I look forward to answering any concerns and also to any offers of help.&nb=

+sp;&nbsp; I used block 542324 of the Bitcoin blockchain to make a memorable=

+ experience using the game of life. I wrote a script for the open-source Ga=

+me-of-Life software Golly and shared it in

+ the paste at <a href=3D"https://pastebin.com/k5Ssc0qk" target=3D"_blank">h=

+ttps://pastebin.com/k5Ssc0qk</a>. It produces the image at

+<a href=3D"https://imgur.com/a/rwIQuVz" target=3D"_blank">https://imgur.com=

+/a/rwIQuVz</a>. If someone can tell me how to get a UTXO Set from the bitco=

+in client, I'll send them $50 of bitcoin. Then I could get the SHA256 hash =

+of that set and try to make a recognizable

+ checkpoint for the Bitcoin blockchain. If someone runs Golly and shares a =

+video of the game playing out (into the apron-shaped image), I'll send them=

+ $50 of bitcoin too.<br>

+<br>

+In a few decades when the blockchain has grown to a few terabytes and the U=

+TXO Set is still just a few gigabytes, I'd like to see more people start ru=

+nning full nodes without the hassle of a long wait and loads of storage spa=

+ce. That's what stops me from running

+ one.<br>

+</div>

+</div>

+</div>

+</blockquote>

+</div>

+<br clear=3D"all">

+<br>

+-- <br>

+<div dir=3D"ltr" class=3D"x_gmail_signature">

+<div dir=3D"ltr">I like to provide some work at no charge to prove my value=

+. Do you need a techie?&nbsp;

+<br>

+I own <a href=3D"http://www.litmocracy.com" target=3D"_blank">Litmocracy</a=

+> and <a href=3D"http://www.memeracing.net" target=3D"_blank">

+Meme Racing</a> (in alpha). <br>

+I'm the webmaster for <a href=3D"http://www.voluntaryist.com" target=3D"_bl=

+ank">The Voluntaryist</a> which now accepts Bitcoin.<br>

+I also code for <a href=3D"http://dollarvigilante.com/" target=3D"_blank">T=

+he Dollar Vigilante</a>.<br>

+&quot;He ought to find it more profitable to play by the rules&quot; - Sato=

+shi Nakamoto</div>

+</div>

+</div>

+</body>

+</html>

+

+--_000_PS2P216MB01795F6E52A18C73E20E9D5A9D160PS2P216MB0179KORP_--

+