The four most famous international exchanges:

Binance INTL	OKX INTL	Gate.io INTL	Huobi INTL
China Line　APP DL	China Line　APP DL	China Line　APP DL	China Line　APP DL

Note: The above exchange logo is the official website registration link, and the text is the APP download link.

April 8 12:19
(UTC), the Bitcoin Cash (BCH) block reward has been halved for the first time. According to the code written into the blockchain, miner rewards will be reduced from 12.5 BCH per block to 6.25 BCH when the block height reaches 630,000
. Miners then quickly abandoned the network.

Miners don't work for free. Managing thousands of mining machines also costs money, time, and electricity. The consequence of the Bitcoin Cash block reward halving is that miners immediately lose 50%
revenue, forcing operators to shut down their machines due to meager profits, or switch to other networks, such as Bitcoin.

According to the cryptocurrency mining data website CoinWarz, at the moment the halving started, the block difficulty and computing power (hash rate) of the Bitcoin Cash network began to plummet in free fall.

The hash rate, or the computing power allocated to mining blocks, reached 785 petahashes per second, down 80% from the April 8 peak of 4001.5 petahashes per second.

Block difficulty, a dynamic measure of the computational difficulty for miners to process blocks, plummeted to 269 billion, nearly 50% lower than the 528 billion on April 8.

Concerns about Bitcoin Cash’s network security have emerged as both block difficulty and hash rate have dropped simultaneously – something LongHash’s Kyle Torpey envisioned last April.

According to data from Crypto51.app, a website that tracks the cost of launching a 51% attack to forge or delete blockchain transaction records, as of April 13, Beijing time
At 16:30, it cost only $9,121 to attack the Bitcoin Cash network for one hour, which was equivalent to the price of 41.11 BCH at the time. It is estimated that the cost of attacking the Bitcoin network during the same period is 52
million, which is 57.39 times that of the attack on Bitcoin Cash. In addition, the cost of attacking the Ethereum network for one hour is $85,377, which is also single digit higher than the cost of attacking Bitcoin Cash.

Crypto51 arrived at these figures by calculating the cost of leasing enough hash power from NiceHash to control 51% of the network. It should be noted that NiceHash alone
There are not enough machines in itself to provide the computing power to occupy a certain mainstream blockchain in the short term, but the point is that the data on this website can quantify the security level of the blockchain network.

Initiate 51%
After the attack, the attacker can easily control the blockchain, and it is easy to withdraw or delete certain transactions. In this case, exchanges or similar service providers are likely to suffer losses, because attackers can deposit coins into these platforms to obtain accounts and credit, and then withdraw the transaction to double-spend the money in their hands. It doubled.

At 20:48 on April 10, Beijing time, BSV also ushered in its first halving. The number of tokens received by miners was reduced from 12.5 BSV per block to 6.25 BSV per block.
—BSV miners’ income dropped by 50% in real terms.

Miners were quick to respond.

24 hours before the BSV halving event, BCH experienced its own halving and experienced a similar trend. At the worst time, its hash rate dropped by 80% and the difficulty dropped by 50%.

Data from BlockChair shows that since the halving, at 16:30 Beijing time on April 13, BSV’s hash rate has dropped from 3.06 exahashes/s to
1.83 exahashes/s, down about 40%. Hash rate measures the computing power miners allocate to the network through hash value.

This is already reflected in the network difficulty, or how difficult it is for miners to process blocks on the blockchain. According to Satoshi.io, network difficulty dropped from 420 x 109 to 212 x 109
.

It is worth mentioning that within 15 hours after the halving, only 35 BSV blocks were mined, which is 55 less than the number of blocks that can be mined in the same period.
indivual. Since the blockchain uses network difficulty to ensure that an average of 6 blocks can be mined per hour, it should continue to dynamically adjust the difficulty to ensure that transactions are processed on time.

The reason why hash rate, difficulty, and block times are falling simultaneously has to do with miner profitability.

This halving resulted in a 50% revenue drop for miners operating on the BSV chain
, forcing operators with meager profits to shut down or move to other networks for mining. Fewer miners means fewer computers to process blocks, ultimately resulting in slower transactions.

With BSV prices falling the coin is now trading almost $40 below BCH, while both network security have rebounded since the hashrate shrank significantly.

Despite the rebound, both chains are much less secure than they were two days ago. Meanwhile, at least according to CoinWarz
, Bitcoin’s hash rate has increased, suggesting that the Bitcoin fork’s halving event has pushed miners to other, more profitable blockchains. In this case, the other blockchain is the Bitcoin blockchain.