<oembed><type>rich</type><version>1.0</version><author_name>npub1c8flqlwmkh5vehm7rfcacurk9x5ggv36vtra2p97thynzfq0vxus5zgzt8</author_name><author_url>https://nostr.ae/npub1c8flqlwmkh5vehm7rfcacurk9x5ggv36vtra2p97thynzfq0vxus5zgzt8</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2020-01-15&#xA;📝 Original message:&gt; Instead of using sidechains, just use channel factories.&#xA;&gt; You do not need to broadcast the entire internal ledgers of those&#xA;services, only their customers need to know those internal ledgers, and&#xA;sign off on the updates of those ledgers.&#xA;&#xA;That&#39;s right, all you need to broadcast is a small proof, a non-interactive&#xA;blockchain suffix proof&#xA;https://eprint.iacr.org/2017/963.pdf&#xA;&#xA;&#xA;&#xA;On Sun, Jan 12, 2020 at 7:33 PM ZmnSCPxj via bitcoin-dev &lt;&#xA;bitcoin-dev at lists.linuxfoundation.org&gt; wrote:&#xA;&#xA;&gt; Good morning Robin,&#xA;&gt;&#xA;&gt;&#xA;&gt; &gt; Good morning ZmnSCPxj,&#xA;&gt; &gt;&#xA;&gt; &gt; Thank you for your detailed feedback! Two topics:&#xA;&gt; &gt;&#xA;&gt; &gt; Lightning vs Sidechains&#xA;&gt; &gt;&#xA;&gt; &gt; ------------------------&#xA;&gt; &gt;&#xA;&gt; &gt; Why an either-or-solution, if we can connect sidechains via the LN to&#xA;&gt; get the best of both worlds?&#xA;&gt; &gt;&#xA;&gt; &gt; The LN works exceptionally great under the following conditions:&#xA;&gt; &gt;&#xA;&gt; &gt; -   you&#39;re always online&#xA;&gt; &gt; -   you have BTC to manage your channels&#39; inbound-capacity&#xA;&gt; &gt; -   you can afford BTC transactions&#xA;&gt; &gt;     -   in your channel is much more than the minimum on-chain TX fees&#xA;&gt; &gt;&#xA;&gt; &gt;         The next Billion users do not fit that category. They are on&#xA;&gt; unreliable cell phone connections and do not have any BTC yet.&#xA;&gt; &gt;         And the more popular Bitcoin becomes, the fewer people can&#xA;&gt; afford LN channels. Even Eltoo requires your funds to be significantly&#xA;&gt; higher than Bitcoin&#39;s TX fees, right?&#xA;&gt; &gt;&#xA;&gt; &gt;         Already today, more and more services like tippin.me,&#xA;&gt; BlueWallet, etc, provide custodial solutions.&#xA;&gt; &gt;         For small amounts, custody is an acceptable workaround. And I&#xA;&gt; love their usability. Install it and immediately I can send you $0.01. Yet,&#xA;&gt; scaling their approach globally does not lead to desirable outcomes, since&#xA;&gt; we&#39;d be back to trusting banks with their Excel sheets.&#xA;&gt; &gt;&#xA;&gt; &gt;         So let&#39;s make their internal ledgers public and trustless, via&#xA;&gt; independent sidechains. Decentralized Blockchains do scale decently up to a&#xA;&gt; couple Million UTXOs. So a couple thousand Sidechains is probably&#xA;&gt; sufficient for a global medium of exchange. Cross-chain communication&#xA;&gt; without requiring cross-chain validation is possible via atomic swaps and&#xA;&gt; through Bitcoin&#39;s LN. That scales because it separates chain-validators&#xA;&gt; from swap-validators.&#xA;&gt; &gt;         Bitcoin&#39;s LN acts as the central settlement layer for efficient&#xA;&gt; cross-chain transactions between all sidechains.&#xA;&gt; &gt;&#xA;&gt; &gt;         So Endusers &#34;living&#34; in sidechains instead of directly in the LN&#xA;&gt; has many advantages:&#xA;&gt; &gt;&#xA;&gt; &gt; -   no bitcoin blockspace required for on-boarding new users&#xA;&gt; &gt; -   no need to lock funds to provide inbound-capacity&#xA;&gt; &gt; -   no need to stay online or pay watch towers&#xA;&gt; &gt; -   no need to store channel histories&#xA;&gt; &gt; -   account balances can be much smaller than BTC TX fees&#xA;&gt; &gt;&#xA;&gt; &gt;     Those are the exact same reasons why BlueWallet built their LndHub.&#xA;&gt; But sidechains can be trustless. Also a generic protocol provides&#xA;&gt; flexibility for sidechain innovations with arbitrary digital assets and&#xA;&gt; consensus rules.&#xA;&gt;&#xA;&gt;&#xA;&gt; Which is why I brought up multiparticipant offchain updateable&#xA;&gt; cryptocurrency systems.&#xA;&gt; The &#34;channel factories&#34; concepts does what you are looking for, except&#xA;&gt; with better trust-minimization than sidechains can achieve.&#xA;&gt; Just replace &#34;sidechain&#34; with either Decker-Wattenhofer or&#xA;&gt; Decker-Russell-Osuntokun constructions.&#xA;&gt; You can even use the Somsen &#34;statechain&#34; mechanism, which rides a&#xA;&gt; Decker-Wattenhofer/Decker-Russell-Osuntokun construction, though its&#xA;&gt; trust-minimization is only very very slightly better than federated&#xA;&gt; sidechains.&#xA;&gt;&#xA;&gt; It is helpful to remember that Poon-Dryja, Decker-Wattenhofer,&#xA;&gt; Decker-Russell-Osuntokun, and all other future such constructions, can host&#xA;&gt; any contract that its lower layer can support.&#xA;&gt; So if you ride a Poon-Dryja on top of the Bitcoin blockchain, you can host&#xA;&gt; HTLCs inside the Poon-Dryja, since the Bitcoin blockchain can host HTLCs.&#xA;&gt; Similarly, if you ride a Decker-Wattenhofer on top of the Bitcoin&#xA;&gt; blockchain, you can host a Poon-Dryja inside the Decker-Wattenhofer, since&#xA;&gt; the Bitcoin blockchain can host Poon-Dryja channels.&#xA;&gt; This central insight leads one to conclude that anything you can put&#xA;&gt; onchain, you an generally also put offchain, so why use a chain at all&#xA;&gt; except as an ultimate anchor to reality?&#xA;&gt; Poon-Dryja is strictly two-participant, while Decker-Wattenhofer limits&#xA;&gt; the practical number of updates due to its use of decrementing relative&#xA;&gt; timelocks: so you put the payment layer in a bunch of Poon-Dryja channels&#xA;&gt; which support tons of updates each but only two participants per channel,&#xA;&gt; and create a layer that supports changes to the channel topology (where&#xA;&gt; changes to the channel connectivity are expected to be much rarer than&#xA;&gt; payments) and is multiparticipant so you can *actually* scale.&#xA;&gt;&#xA;&gt; Instead of using sidechains, just use channel factories.&#xA;&gt; You do not need to broadcast the entire internal ledgers of those&#xA;&gt; services, only their customers need to know those internal ledgers, and&#xA;&gt; sign off on the updates of those ledgers.&#xA;&gt;&#xA;&gt; Regards,&#xA;&gt; ZmnSCPxj&#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;-------------- next part --------------&#xA;An HTML attachment was scrubbed...&#xA;URL: &lt;http://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20200115/48d7ea4b/attachment-0001.html&gt;</html></oembed>