Function used to determine the fee in ARDR, which the bundler will finally pay for each transaction, having the fee in child chain coins received from the transaction.
- MIN_FEE (default value, bundlers in Ardor v2.0 use this function): the Bundler will always pay the minimum protocol fee, no matter how much child chain coins are received from the child transaction.
- PROPORTIONAL_FEE: the Bundler pays fee in ARDR proportionally to the received child chain coins, according to the Minimum Rate. This would give advantage to the bundler versus bundlers using MIN_FEE function in case the transaction creators start competing for block space by specifying higher fee in child chain coins.
- Custom calculators can be developed as add-ons by implementing the Bundler.FeeCalculator interface. Their classes must be listed in the nxt.customBundlingFeeCalculators configuration property.