<oembed><type>rich</type><version>1.0</version><author_name>npub1g6vxlp4e0nyhs2dqxxcryztyf5f5hyuaq93nw4r87zcnv0sdsa0qqsl5wd</author_name><author_url>https://nostr.ae/npub1g6vxlp4e0nyhs2dqxxcryztyf5f5hyuaq93nw4r87zcnv0sdsa0qqsl5wd</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2017-05-22&#xA;📝 Original message:On Mon, May 22, 2017 at 5:19 PM, Paul Sztorc via bitcoin-dev &lt;&#xA;bitcoin-dev at lists.linuxfoundation.org&gt; wrote:&#xA;&#xA;&gt;&#xA;&gt; In the future, when there is no block subsidy, a rich attacker can also do&#xA;&gt; that in mainchain Bitcoin.&#xA;&gt;&#xA;&#xA;I don&#39;t think they are the same.&#xA;&#xA;With Bitcoin, you only get to reverse recent transactions.  If you actually&#xA;reversed 2-3 weeks of transactions, then the Bitcoin price would fall,&#xA;destroying the value of the additional coins you managed to obtain.  Even&#xA;if their was no price fall, you can only get a fraction of the total.&#xA;&#xA;With BMM, you can &#34;buy&#34; the entire reserve of the sidechain by paying&#xA;(timeout) * (average tx fees).  If you destroy a side-chain&#39;s value, then&#xA;that doesn&#39;t affect the value of the bitcoins you manage to steal.&#xA;&#xA;The incentive could be eliminated by restricting the amount of coin that&#xA;can be transferred from the side chain to the main chain to a fraction of&#xA;the transaction fee pay to the bitcoin miners.&#xA;&#xA;If the side chain pays x in fees, then at most x/10 can be transferred from&#xA;the side chain to the main chain.  This means that someone who pays for&#xA;block creation can only get 10% of that value transferred to the main chain.&#xA;&#xA;Main-chain miners could support fraud proofs.  A pool could easily run an&#xA;archive node for the side chain in a different data center.&#xA;&#xA;This wouldn&#39;t harm the performance of their main operations, but would&#xA;guarantee that the side chain data is available for side chain validators.&#xA;&#xA;The sidechain to main-chain timeout would be more than enough for fraud&#xA;proofs to be constructed.&#xA;&#xA;This means that the miners would need to know what the rules are for the&#xA;side chain, so that they can process the fraud proofs.  They would also&#xA;need to run SPV nodes for the side chain, so they know which sidechain&#xA;headers to blacklist.&#xA;&#xA;&#xA;&gt; In point of fact, the transactions *are* validated...by sidechain full&#xA;&gt; nodes, same as Bitcoin proper.&#xA;&gt;&#xA;&gt;&#xA;The big difference is that Bitcoin holds no assets on another chain.  A&#xA;side-chain&#39;s value is directly linked to the fact that it has 100% reserves&#xA;on the Bitcoin main chain.  That can be targeted for theft.&#xA;&#xA;&#xA;&gt; Paul&#xA;&gt;&#xA;&gt;&#xA;&gt; Regards,&#xA;&gt; ZmnSCPxj&#xA;&gt;&#xA;&gt;&#xA;-------------- next part --------------&#xA;An HTML attachment was scrubbed...&#xA;URL: &lt;http://lists.linuxfoundation.org/pipermail/bitcoin-dev/attachments/20170522/56029b8c/attachment.html&gt;</html></oembed>