Bitcoin Roundtable Announcement Thwarts Bitcoin Classic Launch

Bitcoin Classic , the Bitcoin implementation set to double Bitcoin's 1 megabyte block size limit by a hard fork, suffered a significant setback shortly after its official release this week. A group of prominent exchanges, mining pools and other industry players organized under the "Bitcoin Roundtable" collective, stated publicly they will not switch to Bitcoin Classic for the present.

Open Letter

An open letter by the Bitcoin Roundtable, including signatories representing major Bitcoin exchange Bitfinex , ASIC-manufacturer and mining pool BitFury , exchange, wallet service and mining pool BTCC , cloud hashing service Genesis Mining , mining pools F2Pool , BW Pool , Ghash.IO and others, states:

Bitcoin Classic requires a 75 percent hash power activation threshold to activate a block size limit increase. Since the Bitcoin Roundtable collective accounts for more than 60 percent of hash power on the Bitcoin network today, activation seems unlikely unless some of the signatories reverse their positions.

Instead, the letter expresses support for an initial block size limit increase through Segregated Witness. This solution, which was made a first step in Bitcoin Core 's scalability " roadmap ," offers an effective block size limit increase of .6 megabyte to 1 megabyte, along with additional improvements. As one of its main benefits, Segregated Witness can be rolled out as a soft fork, meaning only miners need to upgrade, rather than all nodes on the Bitcoin network.

The letter reads:

Bitcoin Roundtable

Bitcoin Classic was first introduced a month ago by former Bitcoin Foundation board member Olivier Janssens, FinalHash CTO Marshall Long and Bitcoin miner and developer Jonathan Toomim. Shortly after Bitcoin XT lead developer Mike Hearn very publicly denounced Bitcoin a failed experiment, the alternative implementation quickly gained support from major Bitcoin industry players including Coinbase , Blockchain and Bitstamp , as well as Bitcoin Core veterans Gavin Andresen and Jeff Garzik.

Several major mining pools initially endorsed Bitcoin Classic as well, but this support has been nuanced since. In the midst of a crisis atmosphere, mining pools and other companies organized several meetings across the world as well as online to discuss the situation. One of these meetings, the Bitcoin Consensus Round Table organized by BitFury a day after the North American Bitcoin Conference in Miami, formed the basis of what later resulted in the Bitcoin Roundtable letter.

Speaking to Bitcoin Magazine , BitFury CIO Alex Petrov explained:

This call for unity was seconded by cloud hashing service Genesis Mining CFO Marco Krohn.

"There is huge split in the community regarding the block size limit. The dispute has been going on for a while, first with Bitcoin XT and now between Bitcoin Classic and Bitcoin Core. But I think it's important to realize that both sides want Bitcoin to succeed; assuming anyone has bad intentions is not helpful," Krohn said.

And, regarding concrete scaling proposals:


Previously, a subset of the Chinese mining community - most notably including major ASIC-manufacturer and mining pool Bitmain / AntPool - offered Bitcoin Core an alternativeproposal . Rather than switching to Bitcoin Classic, involved companies proposed to raise the block size limit to 2 megabytes, but with a 90 percent hash power support requirement. This sentiment was later echoed by Bitmain co-founder Jihan Wu, who said that AntPool will test Bitcoin Classic but does not support rolling out a hard fork block size limit increase in the short term. And, on its own Internet forum , Bitmain clarified it will not vow loyalty to any development team in specific:

One of the driving forces behind the Bitcoin Roundtable letter, BTCC COO Samson Mow, acknowledged he does not expect a sudden switch to support Bitcoin Classic from mining pools, if there is any switch at all. Rather, he explained that the Bitcoin Roundtable has even broader support than the letter suggests.

"Bitcoin Classic often overstates their support, or misconstrues support for 2 megabytes or a hard fork as support for Bitcoin Classic," Mow said. "Some companies not on the signatory list have given a commitment to not run Bitcoin Classic until we see if Bitcoin Core can adapt. They support the Bitcoin Roundtable, but they would have preferred a more strongly worded request to Core, and so have refrained from signing. That was the compromise we reached."

Mow agreed the main goal right now is to get more clarity from Bitcoin Core on the proposed scalability roadmap, and said the Bitcoin Roundtable group will help to facilitate as needed.


Bitcoin Classic

While the Bitcoin Roundtable letter was a setback, Janssens, listed as "facilitator" in the Bitcoin Classic release notes, has not given up hope for Bitcoin Classic. Addressing visitors of the r/btc subreddit, predominantly frequented by bitcoiners in favor of a hard fork block size increase, Janssens made clear that Bitcoin Classic intends to remain active - even if it does not achieve a hash rate majority in the short term.

Additionally, at least one mining pool so far stated public support for Bitcoin Classic. Slush Pool , accounting for some 4 percent of total hash power, has committed to let individual miners vote on a potential block size limit increase.

Speaking to Bitcoin Magazine , Slush Pool operator Marek "Slush" Palatinus explained:

And the Bitcoin Roundtable signatories, in the end, did not completely exclude a switch to Bitcoin Classic at some point in the future either. If after three weeks the Bitcoin Core development team has not addressed concerns raised by the letter signatories, some of them might still opt to make a switch.

BitFury's Petrov said:


The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.

The views and opinions expressed herein are the views and opinions of the author and do not necessarily reflect those of Nasdaq, Inc.

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