After experiencing a network freeze shortly after halving, Bitcoin Cash may fall victim to another problem soon: the risk of a 51% attack has greatly decreased after the reward cut.
According to f2pool, Bitcoin Cash hash rate has dropped from almost 4,200 pentahashes per second (PH / s) to just 720 PH / s within two days after halving . Although in the past five hours, Bitcoin Cash hash rate has doubled to 1,600 PH / s, it is still almost three times less than its peak.
the Bitcoin Cash hash rate has dropped from almost 4,200 pentahashes per second (PH / s) to just 720 PH / s within two days after halving
This was due to an apparent mass exodus of miners, who decided to abandon the network. This resulted in a drop of more than 80% of the network's processing power (hash rate) in two days. As a result, launching a 51% attack on the BCH currently costs less than $ 10,000.00 (R $ 51,000.00) an hour, raising concerns about network security.
A 51% attack occurs when most miners (50% +1) use their domain over the hash rate to take control of a given network. The lower the total processing power of the network, the lower the cost to implement this attack.
On May 24, 2019, the two largest mining pools in the Bitcoin Cash network - BTC.top and BTC.com - carried out a 51% attack to prevent an entity from exploiting a vulnerability in the network, which would have left some coins “ loose in the net ”.
Risk for Bitcoin?
The cryptocurrency enthusiast community has begun to speculate whether the sharp drop in Bitcoin Cash hash rate is a sign of things to come for Bitcoin, whose network is gearing up for a block reward reduction, to be implemented in approximately 33 days .
“[The] Bitcoin miners are more f *** than Bitcoin Cash miners if the hash rate suddenly drops by 75% in a single day. Bitcoin Cash adjusts your difficulty every 24 hours. Bitcoin adjusts its difficulty every 14 days. Therefore, Bitcoin miners operate at losses for a much longer period, until the network can operate as normal again (unless there are some last-minute panic changes in the difficulty adjustment protocol). ”
Recently, CriptoFácil reported that Bitcoin's hash rate plummeted an impressive 45% during the sharp drop experienced on March 11. However, the network has remained resilient and virtually immune to any 51% attack attempts.