Author: Antoine Riard 2021-10-26 23:44:45
Published on: 2021-10-26T23:44:45+00:00
The proposal to eliminate the mempool was discussed in a recent conversation between Lisa Neigut and glozow. Instead, users would submit their transactions directly to mining pools, preferably over an anonymous communication network such as tor. Mempools are unnecessary when the majority of hashpower and block template creation is concentrated in a semi-restricted set. Removing the mempool would greatly reduce the bandwidth requirement for running a node and naturally resolve all current issues inherent in package relay and rbf rules. However, removing the mempool would complicate solo mining and make BetterHash proposals more difficult. Network mempools constitute a blockspace marketplace where block demand meets the offer in real-time. As transaction proposers are competing with each other to publish, they have an interest to "front-run" each other by querying the pending transactions to the block producers instead of observing only the published blocks. Therefore, good connections to the block producers are now critical and censorship-resistance of the mining endpoints must be guaranteed. A list of endpoints couldn't be static otherwise it's an artificial barrier to enter in the mining competition, and as such a centralization vector. Dynamic, trust-minimized discovery of the mining endpoints assumes an address-relay network, of which the robustness must be high enough against sophisticated sybil attacks.Relying on tor to guarantee the confidentiality of the transaction announcement is raising its own issues. Flowing by default all the bitcoin traffic over tor will change the incentive structure of tor attackers, potentially attracting a new class of attackers able to do deanonymization attacks. Identified mining endpoints make it easier to launch partition attacks, where mining mempools are sent low-feerate clusters of transactions, to prevent the replacement by a better feerate offer. This is especially concerning for L2 nodes with time-sensitive requirements.Lastly, removing the mempool won't solve the current issues inherent with pre-signed transactions under the mempool min fee as ultimately miner's mempools are also finite in memory and a dynamic lower bound must exist to prevent spam. These lower bounds potentially increase after the signature exchange of the time-sensitive transactions. A direct communication channel between block template construction venues and transaction proposers also provides a venue for direct feedback wrt acceptable feerates at the time, which both makes transaction confirmation timelines less variable as well as provides block producers a mechanism for (independently) enforcing their own minimum security budget.
Updated on: 2023-06-15T02:54:31.526860+00:00