Reiner Priggen

Feels like 2017 – If the cryptosphere starts to get used to the saturation of the Ethereum network, with its exorbitant gas costs, Bitcoin could well play us this dirty trick, too. Although its mechanism is different, some transactions with too low fees no longer go through.

The validation of Bitcoin transactions: a precision mechanism

In the process of validating transactions on the Bitcoin network (BTC), mempools act as a buffer . In Proof of Work (PoW) consensus, a mempool performs a sort of pre-sorting between the arrival of transactions and their processing by miners.

On blockchain Bitcoin, each complete node ( Full Node ) has its own MemPool consisting transactions that have reached after propagation on the network.

Transactions that have fees that are really too low (expressed in satoshi per byte or Sat / B ) are not retained by the mempool and / or are not eventually selected by a block miner. These transactions are thus rejected . They must then be resubmitted with more substantial costs , a bit like increasing the price of gas (in Gwei) on Ethereum.

The code Bitcoin is very well designed. It automatically and dynamically adapts the minimum fees of bitcoin core clients, to no longer take into account transactions submitted with fees below this adaptive threshold.

Towards a further increase in Bitcoin transaction fees?

The Bitcoin network seems to be once again a victim of its own success , as it did during the craziest of the last speculative bubble , which took BTC to $ 20,000. A large number of unconfirmed transactions have just occurred in recent days , due to the mechanism explained above.

As we can see below, on the count of unconfirmed transactions, offered by Blochain.com , there were more than 142,000 uncommitted transactions on the day of October 28, 2020 alone. It is not only a record annual , but we even have to go back to the end of 2017 to find similar or higher figures – notably 180,000 unconfirmed transactions in December 2017 .

Bitcoin core nodes with the default settings thus started increasing the minimum mempool fee to 1536 satoshis . Transactions with fees below 1.5 sat / B are purged from the network without being taken into account.