Bitcoin Cash hardfork confirmed

November 13 Bitcoin Cash hardfork rumors confirmed by the developers team: here is the fork, the algorithm and mining difficulty details
31 October 2017   2529

Hardfork

The previously announced Bitcoin Cash hardfork is to be held on Monday, November 13, so that the exchanges, wallets and other software need to upgrade before this date.

As the developers team reports, the original Bitcoin Cash “EDA” allowed Bitcoin Cash to survive as a minority chain but produces wild fluctuations of hashrate, that in its turn prevents consistently fast confirmations for users, and radically shifts the coin issuance schedule.

After careful consideration, we have made the decision to implement a proposal from Bitcoin ABC lead developer Amaury Sechet. Our decision to choose one specific proposal was not easy, because Bitcoin Cash has several independent development teams, and there was a great deal of deliberation between developers from the different groups.
 

Bitcoin Cash developers team

As detailed, two impartial and unconnected testing teams were chosen to work on the algorithm: Bitprim and nChain. These teams conducted their tests separately and came to the same conclusion of which algorithm was most appropriate. 

However, not everyone thinks so. Charlie Lee, Litecoin creator, doubted the transparency of the choice made:

Algorithm and mining difficulty

According to the team, the new DAA algorithm seeks to accomplish the following objectives:

  • Adjust difficulty to hash rate to target a mean block interval of 600 seconds
  • Avoid sudden changes in difficulty when hash rate is fairly stable
  • Adjust difficulty rapidly when hash rate changes rapidly
  • Avoid oscillations from feedback between hash rate and difficulty
  • Be resilient to attacks such as timestamp manipulation

As the developers detail, the algorithm is based on a 144-period simple moving average. The difficulty is adjusted each block, based on the amount of work done and the elapsed time of the previous 144 blocks.

To compute the difficulty, the process begins with the three topmost blocks, and the one with the median timestamp of the three is chosen. Then, the process is repeated with blocks 144, 145, and 146 (blocks of 144-146 height less than the current) and a median timestamp block is again chosen from those 3.

​From these 2 blocks roughly 144 blocks apart, W is defined as the amount of work done between the blocks, and T as the elapsed time between the blocks.  A high-low filter is applied so that T has maximum value of 2 days and a minimum value of .5 days.  This prevents difficulty from changing too abruptly. (Normally 144 blocks takes approximately 1 day).

Wn = W * ExpectedBlockTime / T .
G = (2^256 / Wn) - 1

According to the team, this is the difficulty target.  

Activation of the new consensus rules will be done on a median time stamp basis on blocks that occur after timestamp 1510600000, which corresponds to November 13th, 2:06 PM GMT.

Coinbase to Appear in San Francisco District Court

Exchange representatives must appear in court due to issues related to BCH trading launch in 2017
07 August 2019   131

San Francisco District Court judge Vince Chhabria ruled that the latter showed negligence and “clear incompetence generated by haste” when it started trading in Bitcoin Cash (BCH) on Coinbase. Now Coinbase, apparently, will be forced to stand trial, Bloomberg reports.

So, at the end of 2017, the exchange opened BCH trading, but was forced to suspend operations after 2 minutes due to high volatility and suspicious price increases - the coin began to grow rapidly several hours before the announcement of Coinbase.

Then the company was accused of insider trading, later crypto enthusiasts even began to find confirmation of this.

According to the judge, the users who bought VSN at inflated prices were primarily affected. He noted that the suspension of trading was too hasty and disrupted the normal functioning of the market.

BCH buyers claim that Coinbase could have announced a bid in advance to prevent a price spike, but it did not. The judge agreed with this opinion and noted that shortly before the launch of BCH trading on Coinbase, the Chicago Mercantile Exchange opened trading in bitcoin futures, which could become a factor of too much market participants' recovery.

According to the publication, Coinbase has not yet commented on the court decision.

Recall that in March 2018, a class action lawsuit was filed against the company, in which Coinbase was accused of “artificially overpricing” Bitcoin Cash through trading based on insider data.