URL:
https://github.com/bitcoin/bitcoin/pull/21001) Create COIN_DUST constant, to represent the dust spam limit used.
2) Update COIN_DUST from 0.01 BTC to 0.001 BTC
Rationale: With the increase in bitcoin value (US$13.67 as of this
writing), it seems reasonable to reduce the value level of which we
consider "dust spam."
3) Update TX miner and relay fee defaults to 0.001 / 0.0005 BTC respectively
Rationale: Reflects growth of dust spam in unspent transaction output dataset.
Review of impact:
a) Definition of COIN_DUST reduced from 0.01 to 0.001.
b) Miners who mine with this code will require a fee >= 0.001 to
include TX's with outputs <= COIN_DUST
c) Normal clients will require a fee >= 0.0005 to relay TX's with
outputs <= COIN_DUST
) mentioned that currently 11% unspent output is 0.00000001BTC, 32% is less than 0.0001BTC and 60% is less than 0.001BTC. At the current price of US$13.5, 0.0001BTC worths only $0.00135. These are basically zero-value but take up 1/3 of resources of the network. To discourage these kinds of transaction, an even higher fee (e.g. 0.005BTC) should be charged with outputs < 0.0001BTC