<oembed><type>rich</type><version>1.0</version><author_name>npub1aslmpzentw224n3s6yccru4dq2qdlx7rfudfnqevfck637cjt6esswfqmx</author_name><author_url>https://nostr.ae/npub1aslmpzentw224n3s6yccru4dq2qdlx7rfudfnqevfck637cjt6esswfqmx</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2020-10-20&#xA;📝 Original message:&#xA;Hi Bastien,&#xA;&#xA;Thanks for creating the summary!&#xA;&#xA;While doing this exercise, I couldn&#39;t find a reason why the `reverse&#xA;&gt; upfront payment` proposal&#xA;&gt; would be broken (notice that I described it using a flat amount after a&#xA;&gt; grace period, not an amount&#xA;&gt; based on the time HTLCs are held). Can someone point me to the most&#xA;&gt; obvious attacks on it?&#xA;&gt;&#xA;&gt; It feels to me that its only issue is that it still allows spamming for&#xA;&gt; durations smaller than the&#xA;&gt; grace period; my gut feeling is that if we add a smaller forward direction&#xA;&gt; upfront payment to&#xA;&gt; complement it it could be a working solution.&#xA;&gt;&#xA;&#xA;The &#39;uncontrolled spamming&#39; as you called it in your doc is pretty serious.&#xA;If you want to have fun, you should really try to spin up a bunch of&#xA;threads and keep your outgoing channels fully saturated with max length&#xA;routes going nowhere. I tried it on testnet and it was quite bad. All that&#xA;traffic is fighting for resources which makes it take even longer to unlock&#xA;the htlcs again.&#xA;&#xA;I think that any solution should definitely address this case too.&#xA;&#xA;Your proposal to add a small upfront payment, wouldn&#39;t that allow the&#xA;(arbitrary) grace period to be removed? It would mean that routing nodes&#xA;always need to pay something for forwarding spam, but if they do it quick&#xA;enough (honest nodes) that expense is covered by the upfront payment.&#xA;&#xA;- Joost&#xA;-------------- next part --------------&#xA;An HTML attachment was scrubbed...&#xA;URL: &lt;http://lists.linuxfoundation.org/pipermail/lightning-dev/attachments/20201020/0861166d/attachment-0001.html&gt;</html></oembed>