Matt Corallo <lf-li...@mattcorallo.com> writes: > As an alternative proposal, at various points there have been > discussions around solving the "RBF-pinning" problem by allowing > transactors to mark their transactions as "likely-to-be-RBF'ed", which > could enable a relay policy where children of such transactions would be > rejected unless the resulting package would be "near the top of the > mempool". This would theoretically imply such attacks are not possible > to pull off consistently, as any "transaction-delaying" channel > participant will have to place the package containing A at an effective > feerate which makes confirmation to occur soon with some likelihood. It > is, however, possible to pull off this attack with low probability in > case of feerate spikes right after broadcast.
I like this idea. Firstly, it's incentive-compatible[1]: assuming blocks are full, miners should always take a higher feerate tx if that tx would be in the current block and the replaced txs would not.[2] Secondly, it reduces the problem that the current lightning proposal adds to the UTXO set with two anyone-can-spend txs for 1000 satoshis, which might be too small to cleanup later. This rule would allow a simple single P2WSH(OP_TRUE) output, or, with IsStandard changed, a literal OP_TRUE. > Note that this clearly relies on some form of package relay, which comes > with its own challenges, but I'll start a separate thread on that. Could be done client-side, right? Do a quick check if this is above 250 satoshi per kweight but below minrelayfee, put it in a side-cache with a 60 second timeout sweep. If something comes in which depends on it which is above minrelayfee, then process them as a pair[3]. Cheers, Rusty. [1] Miners have generally been happy with Defaults Which Are Good For The Network, but I feel a long term development aim should to be reduce such cases to smaller and smaller corners. [2] The actual condition is subtler, but this is a clear subset AFAICT. [3] For Lightning, we don't care about child-pays-for-grandparent etc. _______________________________________________ bitcoin-dev mailing list bitcoin-dev@lists.linuxfoundation.org https://lists.linuxfoundation.org/mailman/listinfo/bitcoin-dev