<oembed><type>rich</type><version>1.0</version><author_name>npub1y22yec0znyzw8qndy5qn5c2wgejkj0k9zsqra7kvrd6cd6896z4qm5taj0</author_name><author_url>https://nostr.ae/npub1y22yec0znyzw8qndy5qn5c2wgejkj0k9zsqra7kvrd6cd6896z4qm5taj0</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2017-08-21&#xA;📝 Original message:1. If it only affects &#34;old dust&#34; UTXO&#39;s where the # of coins in the UTXO&#xA;aren&#39;t sufficient to pay some lower quantile of transaction fees, then&#xA;there can be little argument of theft or loss.&#xA;&#xA;2. There&#39;s another use-case for demurrage as well.&#xA;&#xA;Computation power may grow rapidly if quantum computing becomes more&#xA;common.  At some point, Bitcoin may have to change the public key format&#xA;for coins and the POW used.&#xA;&#xA;In order to do this, old coins will have to transact on the network, moving&#xA;their value to a new format, with many more bits in the public key, for&#xA;example.   But since quantum computing isn&#39;t bounded by moore&#39;s law, so&#xA;this may need to be a regular upgrade every X years.   Rather than a&#xA;regular &#34;bit widening hard fork&#34;, the number of bits needed in a public&#xA;address format could be scaled to the difficulty of the new quantum hashing&#xA;algorithm that *also must *now grow in the # of bits over time.   To ensure&#xA;that coins are secure, those with too few bits must drop off the network.&#xA;So the timing for old coin demurrage can effectively be based on the&#xA;quantum POW difficulty adjustments.   As long as the subsequent exponential&#xA;rate of computation increase can be reasonably predicted (quantum version&#xA;of moore&#39;s law), the new rate of decay can be pegged to a number of years.&#xA;&#xA;&#xA;&#xA;On Mon, Aug 21, 2017 at 10:26 AM, Moral Agent via bitcoin-dev &lt;&#xA;bitcoin-dev at lists.linuxfoundation.org&gt; wrote:&#xA;&#xA;&gt; A more forgiving option would be to have coins past a certain age&#xA;&gt; evaporate into mining rewards at some rate, rather than all at once. People&#xA;&gt; might find this approach easier to stomach as it avoids the &#34;I waited 1&#xA;&gt; block to many and all of my coins vanished&#34; scenario.&#xA;&gt;&#xA;&gt; Another approach would to demand that a certain minimum mining fee be&#xA;&gt; included that is calculated based on the age of an input like this idea:&#xA;&gt; https://www.reddit.com/r/Bitcoin/comments/35ilir/&#xA;&gt; prioritizing_utxos_using_a_minimum_mining_fee/&#xA;&gt;&#xA;&gt; This would result in the coins continuing to exist but not being&#xA;&gt; economically spendable, and therefore the UTXO information could be&#xA;&gt; archived.&#xA;&gt;&#xA;&gt; On Mon, Aug 21, 2017 at 9:35 AM, Thomas Guyot-Sionnest via bitcoin-dev &lt;&#xA;&gt; bitcoin-dev at lists.linuxfoundation.org&gt; wrote:&#xA;&gt;&#xA;&gt;&gt; On 21/07/17 03:59 PM, Lucas Clemente Vella via bitcoin-dev wrote:&#xA;&gt;&gt; &gt; 2017-07-21 16:28 GMT-03:00 Major Kusanagi via bitcoin-dev&#xA;&gt;&gt; &gt; &lt;bitcoin-dev at lists.linuxfoundation.org&#xA;&gt;&gt; &gt; &lt;mailto:bitcoin-dev at lists.linuxfoundation.org&gt;&gt;:&#xA;&gt;&gt; &gt;&#xA;&gt;&gt; &gt;     [...] But the fact is that if we want to make bitcoins last forever,&#xA;&gt;&gt; &gt;     we have the accept unbounded UTXO growth, which is unscalable. So&#xA;&gt;&gt; &gt;     the only solution is to limit UTXO growth, meaning bitcoins cannot&#xA;&gt;&gt; &gt;     last forever. This proposed solution however does not prevent&#xA;&gt;&gt; &gt;     Bitcoin from lasting forever.&#xA;&gt;&gt; &gt;&#xA;&gt;&gt; &gt;&#xA;&gt;&gt; &gt; Unless there is a logical contradiction in this phrasing, the proposed&#xA;&gt;&gt; &gt; solution does not improves scalability:&#xA;&gt;&gt; &gt;  - &#34;Bitcoins lasting forever&#34; implies &#34;unscalable&#34;;&#xA;&gt;&gt; &gt;  - &#34;not prevent Bitcoin from lasting forever&#34; implies &#34;Bitcoins lasting&#xA;&gt;&gt; &gt; forever&#34;;&#xA;&gt;&gt; &gt;  - Thus: &#34;not prevent Bitcoin from lasting forever&#34; implies&#xA;&gt;&gt; &#34;unscalable&#34;.&#xA;&gt;&gt; &gt;&#xA;&gt;&gt; &gt; In practice, the only Bitcoin lost would be those whose owners forgot&#xA;&gt;&gt; &gt; about or has lost the keys, because everyone with a significant amount&#xA;&gt;&gt; &gt; of Bitcoins would always shift them around before it loses any luster (I&#xA;&gt;&gt; &gt; wouldn&#39;t bother to move my Bitcoins every 10 years). I don&#39;t know how to&#xA;&gt;&gt; &gt; estimate the percentage of UTXO is actually lost/forgotten, but I have&#xA;&gt;&gt; &gt; the opinion it isn&#39;t worth the hassle.&#xA;&gt;&gt; &gt;&#xA;&gt;&gt; &gt; As a side note, your estimate talks about block size, which is&#xA;&gt;&gt; &gt; determines blockchain size, which can be &#34;safely&#34; pruned (if you are not&#xA;&gt;&gt; &gt; considering new nodes might want to join the network, in case the full&#xA;&gt;&gt; &gt; history is needed to be stored somewhere). But UTXO size, albeit related&#xA;&gt;&gt; &gt; to the full blockchain size, is the part that currently can not be&#xA;&gt;&gt; &gt; safely pruned, so I don&#39;t see the relevance of the analysis.&#xA;&gt;&gt;&#xA;&gt;&gt; I think if we wanted to burn lost/stale coins a better approach would be&#xA;&gt;&gt; returning them to miner&#39;s as a fee - there will always be lost coins and&#xA;&gt;&gt; miners will be able to get that additional revenue stream as the mining&#xA;&gt;&gt; reward halves. I also don&#39;t think we need to worry about doing a gradual&#xA;&gt;&gt; value loss neither, we should just put a limit on UTXO age in block&#xA;&gt;&gt; count (actually I would round it up to 210k blocks as explained below...).&#xA;&gt;&gt;&#xA;&gt;&gt;&#xA;&gt;&gt; So lets say for example we decide to keep 5 210k blocks &#34;generations&#34;&#xA;&gt;&gt; (that&#39;s over 15 years), then on the first block of the 6th generation&#xA;&gt;&gt; all UTXO&#39;s from the 1st generation are invalidated and returned into a&#xA;&gt;&gt; &#34;pool&#34;.&#xA;&gt;&gt;&#xA;&gt;&gt; Given these (values in satoshis):&#xA;&gt;&gt;&#xA;&gt;&gt; Pool &#34;P&#34; (invalided UTXO minus total value reclaimed since last halving)&#xA;&gt;&gt; Leftover blocks &#34;B&#34; (210,000 minus blocks mined since last halving)&#xA;&gt;&gt;&#xA;&gt;&gt; Then every mined block can reclaim FLOOR(P/B) satoshi in addition to&#xA;&gt;&gt; miner&#39;s reward and tx fees.&#xA;&gt;&gt;&#xA;&gt;&gt; If the last block of a generation does not get the remainder of the pool&#xA;&gt;&gt; (FLOOR(P/1) == P) it should get carried over.&#xA;&gt;&gt;&#xA;&gt;&gt;&#xA;&gt;&gt; This would ensure we can clear old blocks after a few generations and&#xA;&gt;&gt; that burnt/lost coins eventually get back in circulation. Also it would&#xA;&gt;&gt; reduce the reliance of miners on actual TX fees.&#xA;&gt;&gt;&#xA;&gt;&gt;&#xA;&gt;&gt; To avoid excessive miner reward initially, for the first few iterations&#xA;&gt;&gt; the value of B could be increased (I haven&#39;t calculated the UTXO size of&#xA;&gt;&gt; the first 210k blocks but it could be excessively high...) or the value&#xA;&gt;&gt; each block can reclaim could be caped (so we would reclaim at an&#xA;&gt;&gt; artificial capacity until the pool depletes...).&#xA;&gt;&gt;&#xA;&gt;&gt;&#xA;&gt;&gt; Regards,&#xA;&gt;&gt;&#xA;&gt;&gt; --&#xA;&gt;&gt; Thomas&#xA;&gt;&gt;&#xA;&gt;&gt; _______________________________________________&#xA;&gt;&gt; bitcoin-dev mailing list&#xA;&gt;&gt; bitcoin-dev at lists.linuxfoundation.org&#xA;&gt;&gt; https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev&#xA;&gt;&gt;&#xA;&gt;&#xA;&gt;&#xA;&gt; _______________________________________________&#xA;&gt; bitcoin-dev mailing list&#xA;&gt; bitcoin-dev at lists.linuxfoundation.org&#xA;&gt; https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev&#xA;&gt;&#xA;&gt;&#xA;-------------- next part --------------&#xA;An HTML attachment was scrubbed...&#xA;URL: &lt;http://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20170821/6c3b768b/attachment.html&gt;</html></oembed>