Published on: 2022-03-12T13:02:24+00:00
In a discussion on the Bitcoin-dev mailing list, Jeremy suggests removing the dust limit from Bitcoin for several reasons. They argue that it is not their business to determine what outputs people want to create and highlight how dust outputs can be used in smart contracts. They also mention the regulatory implications of small HTLCs in lightning channels and the potential use of sats as value markers in colored coin protocols. Jeremy believes that concerns about dust being spam and leading to fingerprinting attacks are not valid. They explain that node operators can change specific settings without altering the source code to remove the dust limit.Pieter Wuille joins the conversation and suggests having a relay policy to avoid economically irrational behavior related to the UTXO set size. However, he acknowledges that consensus rules would need to account for this issue without hardcoded prices or feerates. ZmnSCPxj raises questions about implementing a weight penalty and its impact on mining nodes. It is suggested that miners may refuse to activate such a fork if they see fewer transactions per block on average.The idea of making all dust transactions invalid by some nodes is discussed. A compromise is proposed to keep them in secondary storage for full nodes and a separate Merkle Tree for bridge servers, enhancing performance while reducing the risk of DoS attacks. However, concerns are raised about efficiency and the tradeoff between security and efficiency. The proposal fails to reduce processing compared to outright making all dust transactions invalid. The cost of full nodes in worst-case scenarios should not increase to avoid miners attacking SPV nodes.The discussion shifts to the handling of 1c and 2c coins in traditional currency and their comparison to Bitcoin denominations. It is noted that there is no effective way to round Bitcoin transactions without accepting overpayments as valid. Restrictions on the value of UTXOs in one's own wallet are debated, with arguments against limiting their value. The concern that the dust set of UTXOs slows down block validation during mining is dismissed, suggesting that a faster database should be built instead. Speculation is made about changes to the calculation of block size and the inclusion of what is currently considered dust in the future.In another thread, ZmnSCPxj discusses the idea of lightweight nodes that ignore UTXOs below the dust limit but still validate other transactions. Concerns are raised about how such nodes would handle transactions that spend multiple dust UTXOs and create a single non-dust UTXO. The potential for attacks involving invalid but ignored dust transactions is mentioned.The discussion on the Bitcoin-dev mailing list also covers the value of dust in Bitcoin transactions. There is speculation about the future value and inheritability of dust UTXOs as the value of Bitcoin increases. The possibility of 1 satoshi covering the mining cost despite reductions in sat/B for additional transactions is raised. Different suggestions are made to mitigate the impact of dust, including separating dust UTXOs at the storage level until a solution is found. Ideas are also proposed to decrease vbytes for transactions that consume dust outputs and reduce future maintenance costs.Overall, the discussions revolve around the removal of the dust limit in Bitcoin, concerns about worst-case behavior, the value and handling of dust transactions, and potential solutions to mitigate the impact of dust on the network.Another aspect of the debate on the Bitcoin-dev mailing list involves the dust limit's impact on network centralization. It is argued that the cost of maintaining dust creates an incentive for miners to mine transactions with lower fees, potentially leading to network centralization. To address this, it is suggested that the consensus rules could be adjusted to decrease transaction vbytes for those consuming dust outputs, ensuring that removing them from the system is equivalent to lowering the fee. This would help avoid short-term incentives that promote network centralization at the expense of node operator overhead.During the BitDevs conference in Austin, concerns were raised about the dust limit and its impact on network centralization. It was argued that the rational discount for mining transactions with dust outputs would likely be very small. It was also pointed out that if transaction relaying nodes censor something that a miner would mine, users may seek private/direct relay to the miner, which can be detrimental to privacy and decentralization. The existence of a dust limit was seen as an incentive to increase network centralization immediately.The writer of the context, ZmnSCPxj, discussed the possibility of achieving the dust limit on the LN side by using channel factories. However, it was noted that this could result in a greater number of participants with differing opinions on appropriate feerates. As a result, the actual on-chain feerates for higher layers may become more significant than the dust limit itself.The issue of uneconomical outputs in the LN was also discussed. Currently, commitment outputs with a value below the transaction owner's dust limit plus the HTLC-claim fee are trimmed-to-dust.
Updated on: 2023-07-31T23:37:51.465106+00:00