Liquidity Ads and griefing subtleties

In the exploration of a more efficient payment system, the primary concern is ensuring that buyers have continuous access to receive payments up to a certain size, which hinges on sellers maintaining minimum liquidity. A conceptual solution involves sellers instantaneously replenishing liquidity as it's used by the buyer, but this approach faces practical challenges, particularly with smaller payments where chain fees would become unsustainable.

Current mechanisms like timelocks do not effectively ensure that sellers maintain the required liquidity; they only discourage closing channels when liquidity is present. Rather than relying on timelocks, alternative incentives for sellers might be necessary. One incentive is the potential earnings from routing fees, which could offset the opportunity cost of reserving liquidity for a buyer if there is consistent volume in the direction of the buyer.

The initial period where the seller's liquidity commitment is unproven is critical, and while lease fees can compensate for the risk of low routing fee income during this period, the risk to reputation is more significant for the seller than the buyer. An ideal system would make it easy for buyers to demonstrate any seller impropriety without allowing buyers to unduly tie up seller liquidity.

One mitigation strategy proposed is streaming the lease fee over time, ensuring that if the buyer defaults, the seller can close the channel without being exposed to griefing tactics. This also prevents the seller from exploiting the system by using a small amount of liquidity to defraud multiple users quickly. The email ends with an open question regarding the benefits of incorporating a timelock in this context, suggesting that its utility may be limited within the proposed framework.