<oembed><type>rich</type><version>1.0</version><author_name>npub1m230cem2yh3mtdzkg32qhj73uytgkyg5ylxsu083n3tpjnajxx4qqa2np2</author_name><author_url>https://nostr.ae/npub1m230cem2yh3mtdzkg32qhj73uytgkyg5ylxsu083n3tpjnajxx4qqa2np2</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2015-05-07&#xA;📝 Original message:On Thu, May 07, 2015 at 10:02:09PM +0000, Matt Corallo wrote:&#xA;&gt; OK, so lets do that. I&#39;ve seen a lot of &#34;I&#39;m not entirely comfortable&#xA;&gt; with committing to this right now, but think we should eventually&#34;, but&#xA;&gt; not much &#34;I&#39;d be comfortable with committing to this when I see X&#34;. In&#xA;&gt; the interest of ignoring debate and pushing people towards a consensus&#xA;&gt; at all costs, ( ;) ) I&#39;m gonna go ahead and suggest we talk about the&#xA;&gt; second.&#xA;&gt; &#xA;&gt; Personally, there are several things that worry me significantly about&#xA;&gt; committing to a blocksize increase, which I&#39;d like to see resolved&#xA;&gt; before I&#39;d consider supporting a blocksize increase commitment.&#xA;&gt; &#xA;&gt;  * Though there are many proposals floating around which could&#xA;&gt; significantly decrease block propagation latency, none of them are&#xA;&gt; implemented today. I&#39;d expect to see these not only implemented but&#xA;&gt; being used in production (though I dont particularly care about them&#xA;&gt; being all that stable). I&#39;d want to see measurements of how they perform&#xA;&gt; both in production and in the face of high packet loss (eg across the&#xA;&gt; GFW or in the case of small/moderate DoS). In addition, I&#39;d expect to&#xA;&gt; see analysis of how these systems perform in the worst-case, not just&#xA;&gt; packet-loss-wise, but in the face of miners attempting to break the system.&#xA;&#xA;It&#39;s really important that we remember that we&#39;re building security&#xA;software: it *must* hold up well even in the face of attack. That means&#xA;we need to figure out how it can be attacked, what the cost/profits of&#xA;such attacks are, and if the holes can be patched.  Just testing the&#xA;software with simulated loads is insufficient.&#xA;&#xA;Also, re: breaking, don&#39;t forget that this may not be a malicious act.&#xA;For instance, someone can send contradictory transactions to different&#xA;parts of the network simultaneously to prevent mempool consistency -&#xA;there&#39;s no easy way to fix this. There are also cases where miners have&#xA;different policy than others, e.g. version disagreements, commercial&#xA;contracts for tx mining, etc.&#xA;&#xA;Finally, remember that it&#39;s not in miners&#39; incentives in many situations&#xA;for their blocks to propagate to more than ~30% of the hashing power.(1)&#xA;&#xA;Personally, I&#39;m really skeptical that we&#39;ll ever find a block&#xA;propagation latency reduction technique that sucesfully meets all the&#xA;above criteria without changing the consensus algorithm itself.&#xA;&#xA;&#xA;* How do we ensure miners don&#39;t cheat and stop validating blocks fully&#xA;before building on them? This is a significant moral hazard with larger&#xA;blocks if fees don&#39;t become significant, and can lead to dangerous&#xA;forks. Also, think of the incentives: Why would a miner ever switch from&#xA;the longest chain, even if they don&#39;t actually have the blocks to back&#xA;it up?&#xA;&#xA;* We need a clear understanding of how we expect new full nodes, pruned&#xA;or not, to sync up to the blockchain. Obviously 20MB blocks&#xA;significantly increases the time and data required to sync. Are we&#xA;planning on simply giving up on full validation and trusting others for&#xA;copies of UTXO sets? Are we going to rely on UTXO commitments? What&#xA;happens if the UTXO set size itself increases greatly?&#xA;&#xA;&gt;  * I&#39;d very much like to see someone working on better scaling&#xA;&gt; technology, both in terms of development and in terms of getting&#xA;&gt; traction in the marketplace. I know StrawPay is working on development,&#xA;&gt; though its not obvious to me how far they are from their website, but I&#xA;&gt; dont know of any commitments by large players (either SPV wallets,&#xA;&gt; centralized wallet services, payment processors, or any others) to&#xA;&gt; support such a system (to be fair, its probably too early for such&#xA;&gt; players to commit to anything, since anything doesnt exist in public).&#xA;&#xA;A good start would be for those players to commit to the general&#xA;principles of these systems; if they can&#39;t commit explain why.&#xA;&#xA;For instance I&#39;d be very interested in knowing if services like Coinbase&#xA;see legal issues with adopting technologies such as payment channels&#xA;between hosted wallet providers, payment processors, etc. I certainly&#xA;wouldn&#39;t be surprised if they see doing anythign not on-blockchain as a&#xA;source of legal uncertainty - based on discussions I&#39;ve had with&#xA;regulatory types in this space it sounds like there&#39;s a reasonable&#xA;chance protocol details such as requiring that transactions happen on a&#xA;public blockchain will be &#34;baked into&#34; regulatory requirements.&#xA;&#xA;&gt;  * I&#39;d like to see some better conclusions to the discussion around&#xA;&gt; long-term incentives within the system. If we&#39;re just building Bitcoin&#xA;&gt; to work in five years, great, but if we want it all to keep working as&#xA;&gt; subsidy drops significantly, I&#39;d like a better answer than &#34;we&#39;ll deal&#xA;&gt; with it when we get there&#34; or &#34;it will happen, all the predictions based&#xA;&gt; on people&#39;s behavior today say so&#34; (which are hopefully invalid thanks&#xA;&gt; to the previous point). Ideally, I&#39;d love to see some real free pressure&#xA;&gt; already on the network starting to develop when we commit to hardforking&#xA;&gt; in a year.&#xA;&#xA;Agreed.&#xA;&#xA;&gt; Not just full blocks with some fees because wallets are&#xA;&gt; including far greater fees than they really need to, but software which&#xA;&gt; properly handles fees across the ecosystem, smart fee increases when&#xA;&gt; transactions arent confirming (eg replace-by-fee, which could be limited&#xA;&gt; to increase-in-fees-only for those worried about double-spends).&#xA;&#xA;FWIW I&#39;ve got some funding to implement first-seen-safe replace-by-fee.&#xA;&#xA;1) http://www.mail-archive.com/bitcoin-development@lists.sourceforge.net/msg03200.html&#xA;&#xA;-- &#xA;&#39;peter&#39;[:-1]@petertodd.org&#xA;00000000000000000fe0a96ac84aeb2e4e5c246e947cd8e759bd5fb158a16caf&#xA;-------------- next part --------------&#xA;A non-text attachment was scrubbed...&#xA;Name: signature.asc&#xA;Type: application/pgp-signature&#xA;Size: 650 bytes&#xA;Desc: Digital signature&#xA;URL: &lt;http://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20150507/f6c7c97c/attachment.sig&gt;</html></oembed>