Fee-Based Spam Prevention For Lightning

The calculation provided inquires about the opportunity cost associated with locking a slot on a payment channel for an extended period, specifically two weeks, under the assumption that the node typically facilitates transactions of around 10,000 satoshis (sats) and earns approximately 1 sat per transaction. Given that it's assumed reasonable for a Hash Time Locked Contract (HTLC) to resolve within 2 minutes, the scenario presented explores the implications of occupying a channel slot for a payment potentially taking up to two weeks to finalize, without considering liquidity constraints.

To understand the opportunity cost involved, the calculation multiplies the number of two-minute intervals in two weeks by the earnings per transaction (1 sat). There are 2 minutes in an interval, 60 minutes in an hour, 24 hours in a day, and 7 days in a week, making the formula for the total number of intervals over two weeks as follows: $2 \times 7 \times 24 \times 30$. The result of this formula is then multiplied by the earning per transaction (1 sat), leading to an approximate opportunity cost of 10,000 sats.

This analysis implies that for a party to send 10,000 sats while occupying a slot for up to two weeks, they would need to account for an additional 10,000 sats to compensate for the opportunity cost incurred due to the extended resolution time of the HTLC. This calculation underscores the cost-benefit considerations that nodes must evaluate when dedicating channel resources to long-duration payments, highlighting the significant impact of resolution time on the economic efficiency of operating a node within a cryptocurrency payment network.