<oembed><type>rich</type><version>1.0</version><author_name>npub17fjkngg0s0mfx4uhhz6n4puhflwvrhn2h5c78vdr5xda4mvqx89swntr0s</author_name><author_url>https://nostr.ae/npub17fjkngg0s0mfx4uhhz6n4puhflwvrhn2h5c78vdr5xda4mvqx89swntr0s</author_url><provider_name>njump</provider_name><provider_url>https://nostr.ae</provider_url><html>📅 Original date posted:2020-10-08&#xA;📝 Original message:&#xA;Good morning Antoine and Zman,&#xA;&#xA;Thanks for your answers!&#xA;&#xA;I was thinking dynamic policy adjustment would be covered by the dynamic&#xA;&gt; commitment mechanism proposed by Laolu&#xA;&#xA;&#xA;I didn&#39;t mention this as I think we still have a long-ish way to go before&#xA;dynamic commitments&#xA;are spec-ed, implemented and deployed, and I think the parameters I&#39;m&#xA;interested in don&#39;t require&#xA;that complexity to be updated.&#xA;&#xA;Please forget about channel jamming, upfront fees et al and simply consider&#xA;the parameters I&#39;m&#xA;mentioning. It feels to me that these are by nature dynamic channel&#xA;parameters (some of them are&#xA;even present in `channel_update`, but no-one updates them yet because&#xA;direct peers don&#39;t take the&#xA;update into account anyway). I&#39;d like to raise `htlc_minimum_msat` on some&#xA;big channels because&#xA;I&#39;d like these channels to be used only for big-ish payments. Today I&#xA;can&#39;t, I have to close that&#xA;channel and open a new one for such a trivial configuration update, which&#xA;is sad.&#xA;&#xA;There is no need to stop the channel&#39;s operations while you&#39;re updating&#xA;these parameters, since&#xA;they can be updated unilaterally anyway. The only downside is that if you&#xA;make your policy stricter,&#xA;your peer may send you some HTLCs that you will immediately fail&#xA;afterwards; it&#39;s only a minor&#xA;inconvenience that won&#39;t trigger a channel closure.&#xA;&#xA;I&#39;d like to know if other implementations than eclair have specificities&#xA;that would make this&#xA;feature particularly hard to implement or undesirable.&#xA;&#xA;Thanks,&#xA;Bastien&#xA;&#xA;Le mar. 6 oct. 2020 à 18:43, ZmnSCPxj &lt;ZmnSCPxj at protonmail.com&gt; a écrit :&#xA;&#xA;&gt; Good morning Antoine, and Bastien,&#xA;&gt;&#xA;&gt;&#xA;&gt; &gt; Instead of relying on reputation, the other alternative is just to have&#xA;&gt; an upfront payment system, where a relay node doesn&#39;t have to account for a&#xA;&gt; HTLC issuer reputation to decide acceptance and can just forward a HTLC as&#xA;&gt; long it paid enough. More, I think it&#39;s better to mitigate jamming with a&#xA;&gt; fees-based system than a web-of-trust one, less burden on network newcomers.&#xA;&gt;&#xA;&gt; Let us consider some of the complications here.&#xA;&gt;&#xA;&gt; A newcomer wants to make an outgoing payment.&#xA;&gt; Speculatively, it connects to some existing nodes based on some policy.&#xA;&gt;&#xA;&gt; Now, since forwarding is upfront, the newcomer fears that the node it&#xA;&gt; connected to might not even bother forwarding the payment, and instead just&#xA;&gt; fail it and claim the upfront fees.&#xA;&gt;&#xA;&gt; In particular: how would the newcomer offer upfront fees to a node it is&#xA;&gt; not directly channeled with?&#xA;&gt; In order to do that, we would have to offer the upfront fees for that&#xA;&gt; node, to the node we *are* channeled with, so it can forward this as well.&#xA;&gt;&#xA;&gt; * We can give the upfront fee outright to the first hop, and trust that if&#xA;&gt; it forwards, it will also forward the upfront fee for the next hop.&#xA;&gt;   * The first hop would then prefer to just fail the HTLC then and there&#xA;&gt; and steal all the upfront fees.&#xA;&gt;     * After all, the offerrer is a newcomer, and might be the sybil of a&#xA;&gt; hacker that is trying to tie up its liquidity.&#xA;&gt;       The first hop would (1) avoid this risk and (2) earn more upfront&#xA;&gt; fees because it does not forward those fees to later hops.&#xA;&gt;   * This is arguably custodial and not your keys not your coins applies.&#xA;&gt;     Thus, it returns us back to tr\*st anyway.&#xA;&gt; * We can require that the first hop prove *where* along the route errored.&#xA;&gt;  If it provably failed at a later hop, then the first hop can claim more&#xA;&gt; as upfront fees, since it will forward the upfront fees to the later hop as&#xA;&gt; well.&#xA;&gt;   * This has to be enforcable onchain in case the channel gets dropped&#xA;&gt; onchain.&#xA;&gt;     Is there a proposal SCRIPT which can enforce this?&#xA;&gt;   * If not enforcable onchain, then there may be onchain shenanigans&#xA;&gt; possible and thus this solution might introduce an attack vector even as it&#xA;&gt; fixes another.&#xA;&gt;     * On the other hand, sub-satoshi amounts are not enforcable onchain&#xA;&gt; too, and nobody cares, so...&#xA;&gt;&#xA;&gt; On the other hand, a web-of-tr\*st might not be *that* bad.&#xA;&gt;&#xA;&gt; One can say that &#34;tr\*st is risk&#34;, and consider that the size and age of a&#xA;&gt; channel to a peer represents your tr\*st that that peer will behave&#xA;&gt; correctly for fast and timely resolution of payments.&#xA;&gt; And anyone can look at the blockchain and the network gossip to get an&#xA;&gt; idea of who is generally considered tr\*stworthy, and since that&#xA;&gt; information is backed by Bitcoins locked in channels, this is reasonably&#xA;&gt; hard to fake.&#xA;&gt;&#xA;&gt; On the other hand, this risks centralization around existing, long-lived&#xA;&gt; nodes.&#xA;&gt; *Sigh*.&#xA;&gt;&#xA;&gt; Regards,&#xA;&gt; ZmnSCPxj&#xA;&gt;&#xA;-------------- next part --------------&#xA;An HTML attachment was scrubbed...&#xA;URL: &lt;http://lists.linuxfoundation.org/pipermail/lightning-dev/attachments/20201008/22e78ab2/attachment-0001.html&gt;</html></oembed>