● RBF usability study published: with only about 6% of the transactions confirmed in 2018 signaling support for BIP125 opt-in Replace-by-Fee (RBF), Optech contributor Mike Schmidt undertook an examination of almost two dozen popular Bitcoin wallets, block explorers, and other services to see how they handled either sending or receiving RBF transactions (including fee bumps). Mike Schmidt: Well, speaking of jamming, the next topic from the Summit was Channel jamming mitigation proposals. We don’t know exactly how we would do that, those proofs, and how we would make sure that those proofs cannot be reused, how we would track channel closing differently than just watching onchain. When you are entering into the exciting world of digital currency, you must know that Bitcoin is the future. There are two research papers that have proposals on how to do that by modifying the scripts that we use in the corresponding output in the commitment transaction. That’s why we’re not doing that right now, and that’s why most people will just keep announcing the output that really corresponds to the channel so that when it gets spent, people actually notice it and can remove it from that graph and know that they cannot route through that channel anymore.
We’ve spoken previously, over maybe six months a bunch of different times, about different kinds of channel jamming attacks: liquidity jamming attacks, which exhaust the capacities in channels; and HTLC jamming attacks, where the attacker attempts to take all the HTLC slots with a bunch of small payments. So, those are things that we’ve always been just hand-wavy about how we would do that in the future. And also another issue with redundant overpayment is that you are actually, for the duration of your payment, using more liquidity of the network than what is required. Each unit is produced or “mined” by using special software to solve complex mathematical problems, a requirement deliberately analogous to the labor involved in mining gold or other precious metals. Before each block of transactions becomes part of the accepted Bitcoin ledger, or block chain, the mining software must transform the data using cryptographic hash equations. PTLC fixes that by making sure that instead of using the preimage of a SHA256 hash and its hash, we’re going to use elliptic curve points and their private keys. So a first version of PTLC will not have redundant overpayment, in my opinion, because there are different ways that could be achieved, and they have different trade-offs that need to be explored a bit more.
Spear is the H2TLC, or something like that, which can be converted into PTLC. For many of the questions/misconceptions discussed in this article, there are digital asset specialists that can answer them with more detail than I can. And they’re going to be tweaked at every hop, which means that even if you have multiple nodes that are on the path of the same payment, it’s not going to be payment hash, you’re going to see a different point, a different secret than in both nodes. Bastien Teinturier: Yeah, and even if it was only 50% more or even 20% more, that could be considered jamming as well. Bastien Teinturier: Okay, so PTLCs are a change that is allowed by taproot and adaptor signatures. Mike Schmidt: Next section from the Summit discussed PTLCs and redundant overpayments. Mike Schmidt: And those techniques that you mentioned, is that the boomerang and the spear that we mentioned in the newsletter? So the one, Bastien, you’re talking about, I think that’s spear actually. So it’s like 100% of liquidity required, then 200%, then 300%. Whereas boomerang and spear allow you to do essentially fractions above a 100%, is that right? While it’s currently early adopters like Reddit, the clear financial upside of Bitcoin for merchants will fuel adoption.
While Binance has frequently sought to promote its role in freezing crypto assets obtained through theft and routed through its platform, it has also faced accusations of facilitating money laundering. So, what if you could instead send more than what you are actually trying to send to increase the likelihood that at least the required amount gets to the destination, but while preventing the recipient from claiming more than what you intended them to have. So, unless there’s obvious timing, amount, and expiry values that lets you know that this is actually the same payment, at least the cryptography of the secrets that are shared will not let you correlate those two payments. But that doesn’t mean there are no servers keeping track of bitcoins. So, this is quite hard to do correctly, and there are proposals. And right now, it’s going to use the same payment hash with all these nodes, which means that if someone owns two of the nodes in the path, 바이낸스 수수료 (check) they are learning information, and this is bad for privacy.
