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NO2X: Next Week’s Hard Fork Has Been “Suspended” Due to a Lack of Consensus

November 8, 2017 Aaron van Wirdum 0


There will almost certainly be no Bitcoin hard fork next week: the main organizers behind the SegWit2x project have “suspended” their efforts.

In an email to the SegWit2x mailing list, one of the main organizers behind the project, BitGo CEO Mike Belshe, explained that the proposed hard fork has not been able to gain sufficient consensus to proceed:

“Although we strongly believe in the need for a larger blocksize, there is something we believe is even more important: keeping the community together. Unfortunately, it is clear that we have not built sufficient consensus for a clean blocksize upgrade at this time.”

The New York Agreement was originally forged between a group of Bitcoin companies in May of this year. An initiative by Digital Currency Group CEO Barry Silbert, the project — later dubbed “SegWit2x” — was to combine activation of the Segregated Witness soft fork with a hard fork to double Bitcoin’s block weight limit. With Segregated Witness activated on the Bitcoin network this past summer, arguably helped by the SegWit2x project, the hard fork was scheduled to take place next week.

However, the hard fork part of the New York Agreement was always controversial for a number of reasons. As a result, a growing number of signatories dropped out of the agreement over the past weeks and months, while developers, user communities, public polls, future markets and more all indicated limited support for the effort. And as the hard fork date drew closer, it become increasingly clear that SegWit2x would in fact spawn a new currency rather than constitute an upgrade of the Bitcoin protocol.

And this was never the plan, Belshe wrote:

“Continuing on the current path could divide the community and be a setback to Bitcoin’s growth. This was never the goal of Segwit2x.”

Belshe’s email was also signed on behalf of Xapo CEO Wences Casares, Bitmain CEO Jihan Wu, Bloq CEO Jeff Garzik, Blockchain CEO Peter Smith and ShapeShift CEO Erik Voorhees. In a separate blog post published just before Belshe’s email, BitPay CEO Stephen Pair also called for cancelation of the hard fork.

While the New York Agreement was signed by even more companies (and some individuals), and anyone can still deploy the hard fork, it is unlikely that anyone will proceed with the hard fork in any meaningful way.

Belshe does, however, note that a hard fork to increase Bitcoin’s block weight limit might be needed in the future, writing:

“As fees rise on the blockchain, we believe it will eventually become obvious that on-chain capacity increases are necessary. When that happens, we hope the community will come together and find a solution, possibly with a blocksize increase.”

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These International Bitcoin Communities Are Rejecting SegWit2x

October 31, 2017 Aaron van Wirdum 0

These International Bitcoin Communities Are Rejecting SegWit2x

The hard fork part of the New York Agreement is scheduled to take place within about two weeks. This incompatible protocol rule change is set to increase Bitcoin’s block weight limit, to allow for more transactions on the network — if everyone adopts the change. Otherwise, it will create a new blockchain and currency that may or may not be considered to be “Bitcoin.”

The list of signatories of this agreement includes several of the largest Bitcoin startups and mining pools that, together, claim to represent a majority of users and hash power. Yet, it is far from clear that this 2x part of SegWit2x proposal really has much support outside of these signatories. Most of Bitcoin’s development community, a significant number of other companies, some mining pools, user polls as well as futures markets suggest otherwise.

And now, a growing list of international Bitcoin communities is putting out public statements against the SegWit2x hard fork as well.

An overview…

Seoul Bitcoin Meetup

On October 12, 2017, the Seoul Bitcoin Meetup — the largest and longest-running Bitcoin meetup in South Korea with over 1700 members — was the first user community to put out a statement on SegWit2x. More precisely, in their own words, the group voiced its “staunch opposition to this November’s proposed hardfork.”

In its statement, the Seoul Bitcoin Meetup places emphasis on the manner in which the agreement was made. Typically, changes to the Bitcoin protocol go through the Bitcoin Improvement Proposal (BIP) process where it is peer reviewed by developers across the ecosystem, whereas SegWit2x went through the New York Agreement, which was forged at an invite-only meeting among about a dozen company executives.

The Seoul Meetup states:

If a select group of CEOs and investors, no matter how benevolent their intentions, can unilaterally make decisions about the consensus rules without public comment and force these changes upon the network regardless of overall consensus, then Bitcoin will have lost the properties that make it valuable in the first place.

Additionally, the Seoul Bitcoin Meetup argues that the hard fork is needlessly risky without offering sufficient benefits to warrant the risk. It also takes issue with the controversial decision of SegWit2x developers not to implement strong replay protection.

Bitcoin Meetup Munich

On the same day as the Seoul Meetup Group, the Bitcoin Munich meetup group also put out a public statement against the SegWit2x hard fork. This meetup group consists of over 2000 members — though only several dozen of them actually engaged in the vote whether or not the statement against the SegWit2x hard fork would be accepted. This statement itself was spread via photo on social media.

In its statement, the Bitcoin Munich meetup explains it opposes the SegWit2x hard fork in part because of technical concerns:

Another doubling of the block size so quickly after SegWit seems hasty and might cause further mining centralization.

The statement further argues that a hard fork requires more and better preparation and should include more improvements from the hard fork wish list, and it endorses Bitcoin Core as “the true Bitcoin client.”

Brazilian and Argentinian Bitcoin Communities

The biggest user community also published the longest statement against the SegWit2x hard fork so far. A combined effort between a significant group of Argentinian and Brazilian users and companies, published on October 17,2017, voiced “their deepest concerns over the upcoming November hardfork as mandated by the so-called New York Agreement (NYA), also known as SegWit2x (S2X).”

Not unlike other critics of the hard fork, emphasis was placed on the process that led to the SegWit2x agreement:

The very nature of an ‘agreement’ between a few parties in a decentralized consensus protocol can be interpreted as an aggression against the network.

Similarly, the statement addresses the lack of transparency from SegWit2x proponents, criticizing the notion of a “political compromise instead of a technical upgrade” and the “consensus imposition instead of consensus building.”

Other points of concern include the lack of replay protection, the rushed nature of the hard fork, misleading statements by SegWit2x proponents and much more.

Israeli Bitcoin Association

The Israeli Bitcoin Association is a non-profit organization that promotes Bitcoin and similar technologies in Israel, with an open membership. On October 24, 2017, this association put out its own statement on the SegWit2x hard fork.

Slightly different from several of the other statements, the Israeli Bitcoin Association emphasizes the right of anyone to fork Bitcoin and create a new cryptocurrency. That naturally includes SegWit2x proponents.

But importantly, the association adds:

A protocol change in the currency holding the name ‘Bitcoin’, especially one requiring a hard fork, requires overwhelming consensus. The SegWit2x hard fork does not in any way enjoy such consensus, and while this remains the case we cannot refer to the resulting currency as ‘Bitcoin.’

The SegWit2x currency will instead be referred to as “‘Bitcoin2x.’ ‘SegWit2x coins,’ BT2, B2X, S2X or any other distinctive term that the industry will adopt.”

The Hong Kong Bitcoin Community / Bitcoin Association of Hong Kong

The Hong Kong Bitcoin Community in general, and the Bitcoin Association of Hong Kong specifically, put out statements against SegWit2x on October 25, 2017.

While technically separate statements, both voice their concern about the lack of consensus for the hard fork. The Hong Kong Bitcoin Community — a group of Hong Kong–based companies — states that “the lack of enthusiastic support for this fork among the community is striking.” The association — which mostly exists to promote Bitcoin in Hong Kong — states that “the proponents of the hardfork should kindly ask the Bitcoin community to support them and then only proceed with the hardfork if there is widespread community support.”

Additionally, the Hong Kong groups speak out against the lack of replay protection in the SegWit2x fork.

Due to the combination of both a lack of consensus across the community and a lack of strong replay protection, we consider SegWit2x a reckless endeavor that will cause disruption and harm to the ecosystem.

The Italian Bitcoin Community

The Italian Bitcoin community, more specifically a group of companies, meetups, lobbying groups and other organizations, put out a statement against SegWit2x on October 31, 2017.

The statement is largely inspired by an earlier statement by the Italian blockchain research lab BHB, which rejected SegWit2x as “an attempt to perform a political takeover of Bitcoin.”

The statement by the broader Italian Bitcoin community is a bit more compact, but nonetheless touches on many of the familiar points of criticism regarding the SegWit2x hard fork.

It reads:

The opposition is especially strong against any action of this kind that could cause huge inconveniences for service providers and serious confusion for users, potentially leading to financial losses: unilateral attempts to appropriate Bitcoin name, logo or “ticker”, attempts to mislead light-clients and SPV wallets on alternative networks not explicitly chosen by them, attempts to launch new coins in a way which leave users vulnerable to “replay attacks” or address format confusion, attempts to attack the network with a temporary hashing-power majority in order to create disruptive reorgs or to slow down the normal activity.

French-Speaking Bitcoin Communities

Meanwhile, the French-speaking Bitcoin communities are voicing their concerns with the SegWit2x hard fork through a petition. It is currently signed by over 1300 people and counting.

The (French) text that accompanies the petition is mostly inspired by and based on the statement published by the Seoul Bitcoin Meetup. Like that statement, this petition emphasizes concerns about the manner in which the agreement was forged, while also noting the lack of replay protection and other problems.

Additionally, the petition includes a call to action to find alternatives for the companies that signed onto and continue to support the SegWit2x hard fork:

We would suggest avoiding the use of services of companies that support the NYA, and we hope to substitute them with alternative solutions.

Are they any more user communities that have put out statements against or in favor of the SegWit2x hard fork? Let me know at

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To B2X or Not to B2X: How Exchanges Will List the SegWit2x Coin

October 28, 2017 Aaron van Wirdum 0


The SegWit2x hard fork is drawing closer by the day. Within little over two weeks after the publication of this article, a group of Bitcoin companies and miners plans to double Bitcoin’s block weight limit as per the New York Agreement.

But it currently seems certain that not everyone will adopt this incompatible protocol change. As such, the SegWit2x fork would result in two different blockchains and two different currencies. For the purpose of this article, these two blockchains will be referred to as the “original chain” and the “SegWit2x chain,” with their respective coins.

The big question, right now, is which of these two blockchains would be considered the “real” Bitcoin, with the currency ticker “BTC.” Since no single individual or entity is really in charge of this decision, Bitcoin exchanges play a major role: they list the currencies that are traded under specific names.

To find out which coin is likely to earn the ticker “BTC,” here’s an overview of the 20 largest Bitcoin exchanges based on trading volume according to data from Bitcoinity, and their stance on this naming issue.

1. Bitfinex: original chain is “BTC”, SegWit2x chain is “B2X”

Hong Kong–based cryptocurrency exchange Bitfinex is the largest Bitcoin exchange in the world by trading volume.

Interestingly, Bitfinex also offers a futures exchange, on which claims on the future versions of the coins on both chains are already traded. These futures are currently labeled as “BT1” for coins on the original chain, and “BT2” for coins on the SegWit2x chain.

In Bitfinex’s announcement of these futures, published on October 5, as well as the accompanying terms and conditions, the exchange also reveals that “the order books for the BT2 trading pairs will become the order books for the B2X pairs.” Meanwhile, the BT1 futures will be settled into BTC.

In other words, the coins on the original chain will be listed as “BTC”, while the coins on the SegWit2x chain will be called “B2X.”

2. BitMEX: original chain is “BTC”

BitMEX, a cryptocurrency exchange officially based in the Republic of Seychelles, is the second-largest Bitcoin exchange in the world based on trading volume.

In a blog post published on October 13, BitMEX announced it would continue to list coins on the original chain as “BTC.”

Moreover, because SegWit2x will not implement strong replay protection, BitMEX will not list coins on the SegWit2x chain at all, nor offer any other type of support.

3. Bitstamp: unknown

Bitstamp, which is officially based in the United Kingdom but operates from several European countries, has not yet made any public statements concerning the SegWit2x fork. The exchange also did not respond to inquiries from Bitcoin Magazine.

Bitstamp did sign a hard fork statement insisting on consensus and strong replay protection for hard forks earlier this year, though that statement referred to a potential Bitcoin Unlimited hard fork — not SegWit2x.

4. GDAX: hash power decides which chain is “BTC”

U.S.-based cryptocurrency exchange GDAX is effectively the exchange-arm of Coinbase. And Coinbase is a signatory of the New York Agreement.

Regardless, it’s not certain that Coinbase (and therefore probably also GDAX) will list coins on the SegWit2x chain as “BTC.” In fact, the company could well list the coins on the original chain as “BTC” — but public statements have been somewhat contradictory.

The company initially put out a statement saying that the coins on the original chain would be listed as “BTC,” and the coins on the SegWit2x chain as “B2X.” However, this initial statement was effectively withdrawn the very next day, as the company put out a new statement “clarifying” that Coinbase will actually list the coins with the most accumulated hash power backing it as “BTC.” And on Twitter, company CEO Brian Armstrong suggested that it’s not just hash power but also market cap that will decide which coin will be listed as “BTC.”

5. bitFlyer: unknown

bitFlyer is the biggest Bitcoin exchange in Japan.

bitFlyer is also a signatory of the New York Agreement in support of the SegWit2x hard fork, which suggests that the exchange will at least support the coin on the SegWit2x chain. bitFlyer has not yet made any public statements concerning the naming of the coin(s), however, and did not respond to inquiries from Bitcoin Magazine.

6. Kraken: unknown

U.S.-based Bitcoin and cryptocurrency exchange Kraken has not yet made any public statements concerning the SegWit2x fork, either.

In response to inquiries from Bitcoin Magazine, the exchange also refrained from commenting on the naming issue and instead stated:

“Kraken makes no promises/guarantees/warranties on the outcome of the fork. We will make our best effort to handle things in a way that benefits the most clients, but clients should manage their own wallets/coins if they want perfect control.”

7. HitBTC: original chain is “BTC”, SegWit2x chain is “B2X”

Like Bitfinex, cryptocurrency exchange HitBTC is already offering a futures market where the two future coins are traded.

And in an announcement published on October 17, the exchange said it will list the coins on the SegWit2x chain as “B2X.” The coins on the original chain will continue to be listed as “BTC.”

However, HitBTC does note that the “Bitcoin community might encourage ‘BTC’ title being relocated to the SegWit2x token.” They added: “Whatever happens, we will proceed with the decision that will be the most convenient for our traders.”

8. unknown

The German Bitcoin exchange has not yet made any public statements concerning the SegWit2x fork. The exchange also did not respond to inquiries from Bitcoin Magazine.

9. CoinsBank (formerly known as BIT-X): original chain is “BTC”

United Kingdom–based cryptocurrency exchange CoinsBank (formerly known as BIT-X) has not made any public statements concerning the SegWit2x fork.

In response to inquiries from Bitcoin Magazine, however, the exchange indicated that it will list coins on the original chain as “BTC” and will not support the SegWit2x chain.

They stated:

“We inform you that we are proponents of the BTC core and not planning to support other branches.”

10. CEX.IO: original chain is “BTC”, SegWit2x chain is “B2X”

United Kingdom–based Bitcoin exchange CEX.IO will list coins on both chains. In a blog post published on October 20, the exchange announced it will list the coins on the SegWit2x chain as “B2X.” It also states in the announcement that coins on the original chain will continue to be listed as “BTC.”

11. itBit: unknown

U.S.-based Bitcoin exchange itBit has not yet made any public statements concerning the SegWit2x fork. The exchange also did not respond to inquiries from Bitcoin Magazine.

12. Gemini: hash power decides which chain is “BTC”

In an October 24 blog post written by Cameron Winklevoss, one Gemini’s founders, the U.S.-based Bitcoin exchange explained that it “will be measuring total cumulative computational difficulty of the blockchain to determine what we will call Bitcoin and BTC and on the Gemini platform.”

In other words, Gemini will give the name “BTC” to the coin that has the most hash power attributed to it.

It may also list the coin that does not attract the majority of total hash power, but the exchange has not given any guarantees yet, nor did it mention a name for this coin.

13. Coinfloor: unknown

U.K.-based Bitcoin exchange Coinfloor has not yet made any public statements concerning the SegWit2x fork. The exchange also did not respond to inquiries from Bitcoin Magazine.

Coinfloor did sign the hard fork statement insisting on consensus and strong replay protection for hard forks, which originally referred to the potential Bitcoin Unlimited hard fork.

14. BTCC: unknown

Like Bitfinex and HitBTC, Hong Kong–based Bitcoin exchange BTCC is already offering a futures market where the two future coins are traded. These coins are currently referred to as “1MB” for the coin on the original chain, and “2MB” for the coin on the SegWit2x chain.

However, as opposed to Bitfinex and HitBTC, BTCC has not announced what it will call the two coins after the split has occurred. The exchange also did not immediately respond to inquiries from Bitcoin Magazine.

15. BitMarket: unknown

Polish Bitcoin exchange BitMarket has not yet made any public statements concerning the SegWit2x fork.

The exchange did respond to inquiries from Bitcoin Magazine, but it did not reveal which coin will be listed under what name or ticker.

Instead, a BitMarket representative stated:

“We reserve the right to decide whether to support or not [the] given fork of the Bitcoin. Our decision will depend on the stability of the fork’s network and what issues it may cause in the future.”

16. QuadrigaCX: unknown

Canadian Bitcoin exchange QuadrigaCX has not yet made any public statements concerning the SegWit2x fork. The exchange also did not respond to inquiries from Bitcoin Magazine.

QuadrigaCX did sign the hard fork statement insisting on consensus and strong replay protection for hard forks, originally referring to the potential Bitcoin Unlimited hard fork.

17. Mercado Bitcoin: original chain is “BTC”

Brazilian Bitcoin exchange Mercado Bitcoin recently signed a statement on behalf of the Brazilian and Argentinian Bitcoin communities in opposition of SegWit2x.

When asked by Bitcoin Magazine, the exchange further explained that it may or may not list the coins on the SegWit2x chain, which will in part depend on whether or not the SegWit2x chain implements strong replay protection. (This currently seems very unlikely.)

If Mercado Bitcoin does list this coin, it will use the ticker “B2X” because “the market is converging to this ticker.” They added: “We also tend to consider the Core version the legitimate one.”

18. Bitso: unknown

Mexican Bitcoin exchange Bitso is a signatory of the New York Agreement in support of the SegWit2x fork. The company has since also confirmed that it will support coins on both chains — even though it did sign the Bitcoin Unlimited–inspired hard fork statement insisting on consensus and strong replay protection for hard forks.

Regarding names and tickers, a Bitso representative told Bitcoin Magazine:

“We have not yet decided on ticker names but hope to make an official statement soon.”

19. The Rock Trading: original chain is “BTC”

Malta-based Bitcoin exchange The Rock Trading has not yet made any public statements concerning the SegWit2x fork. It did, however, sign the Bitcoin Unlimited–inspired hard fork statement insisting on consensus and strong replay protection for hard forks.

And, when asked by Bitcoin Magazine, The Rock Trading CTO Davide “Paci Barbarossa” Barbieri said the exchange will list the coins on the SegWit2x chain as “B2X” — if the exchange lists that coin at all.

Said Barbieri:

“As stated publicly, we are generally against any hard forks; we do not currently guarantee that we will handle SegWit2x, or that we will list it; as far as I know replay protection is still a concern.”
And: “If we do [list the coin on the SegWit2x chain] we will probably call it B2X or something like it.”

20. EXMO: unknown

U.K.-based cryptocurrency exchange EXMO has not yet made any public statements concerning the SegWit2x fork. The exchange also did not respond to inquiries from Bitcoin Magazine.

This article will be updated as the news develops. Did I miss anything? Feel free to let me know at

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What Lightning Will Look Like: Lightning Labs Has Announced Its User Interface Wallet

October 19, 2017 Aaron van Wirdum 0

What Lightning Will Look Like: Lightning Labs Has Announced Its User Interface Wallet

Development of the lightning network, the lightning networkthe highly-anticipated second-layer Bitcoin protocol for instant microtransactions, continues to inch forward.

Lightning Labs, major contributor to the lightning network daemon, lnd, announced its cross-platform Lightning Desktop App last week. The open-source lightning wallet is essentially a user interface (UI) built on top of lnd and powered by Lightning Labs’ new open-source Bitcoin light client, Neutrino.

“This is the first functioning user interface for both sending and receiving lightning transactions with a light client mode,” Lightning Labs CEO Elizabeth Stark told Bitcoin Magazine.

The lightning network is currently being developed by several teams working on different but interoperable implementations of the protocol. Several of these implementations are functional, though only on Bitcoin’s test network (“testnet”): a sort of copy of the Bitcoin network with valueless coins specifically designed for testing new applications and more.

But, while there are already several lightning daemons available for testnet, most are only usable via command line tools. Developers Olaoluwa Osuntokun, Bryan Vu and Case Sandberg collaborated to now extend lnd with the new Lightning Desktop App to provide a user interface.

“I think the big takeaway is being able to visualize this technology and see what an early UI might look like,” said Stark. “It’s one thing to be using the command line, as our lnd testers and developers have been, but it’s another to be able to download the app. Being able to see this kind of progress is important.”

As part of the announcement, Lightning Labs also introduced Neutrino, the new open-source Bitcoin implementation that powers the Lightning Desktop App. As a main benefit, Neutrino users don’t need to download the entire Bitcoin blockchain, which is currently over 140 gigabytes in size. This makes the desktop app much more accessible to regular users who transact small amounts, for which the lightning network is particularly suited. And because Neutrino uses a new method of transaction filtering (client side instead of bloom filters), it offers more privacy than most light clients, too.

The release of the new Lightning Desktop App kicks off a two-week “testing blitz,” as the company described it in their accompanying blog post. Developers are invited to experiment with the desktop app itself, as well as with Neutrino. Further, it makes it much easier for anyone to play around with lnd and the lightning network itself.

“The really cool thing about having our desktop app out there is now there’s an easy way for people to interact with all of the apps that developers are building on Lightning, such as Yalls,” said Stark.

After the two-week testing period, the implementation will enter a regular release cycle. Releasing the wallet for Bitcoin mainnet, however, could take a while longer still, Stark explained:

“We’re working toward testing and making the software more stable before releasing a beta. This is financial software and its a protocol dealing with money, so we want to ensure people can have a good user experience.”

There is no specific deadline for the beta release, but Stark added that, “The next step is for us to gather feedback from testers and develop it further, along with improvements in lnd and Neutrino.”

The open-source Lightning Desktop App code is available on GitHub.

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Chaincode Labs to Host a Second Run of Its Month-Long Bitcoin Coding Class

October 18, 2017 Aaron van Wirdum 0

Chaincode Labs to Host a Second Run of Its Month-Long Bitcoin Coding Class

Chaincode Labs, the New York–based development company and major contributor to Bitcoin Core, is organizing a second edition of its Bitcoin residency program in the first months of 2018. The program intends to help developers overcome the steep learning curve associated with becoming a protocol-level contributor to projects like Bitcoin Core. In doing so, Chaincode Labs hopes to help expand Bitcoin’s development community.

“Last year was the first run,” Chaincode Labs developer John Newbery told Bitcoin Magazine. “We’ve now taken the good stuff from that and tried to make it even more focused and useful for residents this year.”

The Residency Program

Chaincode Labs, in collaboration with Matt Corallo — who worked at Blockstream last year but joined Chaincode Labs since — organized the residency program for the first time in September and October of 2016. The next edition will start on January 29, 2018, and will last until February 23.

Newbery himself was one of the attendees of this first residency program. He was later hired by Chaincode Labs and has since been one of the most prolific contributors to the Bitcoin Core project.

Now, he is coordinating the second of two legs of the new program.

“Chaincode Labs exists to strengthen Bitcoin,” said Newbery. “We mostly do that by contributing to Bitcoin Core, but each of us has a lot of freedom to do what we think is important. And the main purpose of this residency program is to try to strengthen the developer community.”

Specifically, courses will cover protocol design, adversarial thinking, threat models and security considerations, as well as address some of Bitcoin’s biggest challenges, like scaling, fungibility and privacy. Attendees will mostly learn by doing and could even start contributing to the Bitcoin Core project during the residency. Throughout the program they will be assisted by the entire Chaincode Labs team — Alex Morcos, Suhas Daftuar, Matt Corallo, John Newbery and Russ Yanofsky. There may also be guest speakers.

Two Blocks

Whereas the first edition of the residency program lasted four straight weeks for all attendees, this time the coding classes will be cut into two two-week phases. Candidates can either pick one of two legs or join both, with room for five or six attendees per session.

The first leg is coordinated by Corallo, who has been contributing to Bitcoin development since 2011.

“Session A is all about getting people to think about the security trade-offs and implications of the technical decisions we make,” Newbery explained. “There’s a lot of thought that goes into all the decisions that are made in Bitcoin, but that nuance is often lost. If we can help people to understand those trade-offs better and be able to communicate them, then perhaps we can raise the level of the conversations we have about Bitcoin.”

The second session will be more focused on the Bitcoin Core project itself, Newbery said.

“Session B is all about getting smart, talented people to start making useful contributions to Bitcoin Core. There’s a steep learning curve to becoming a contributor and if I can help people who want to contribute but have felt daunted or don’t know where to start, then I’ll feel like I’ve succeeded.”

Additionally, Chaincode Labs will organize a series of Wednesday night meetups ahead of the residency program. Contents of these meetups will be similar to the residency program, but these meetups are for participants who live in (or near) New York who can’t dedicate two or four full weeks to attending the residency program itself.

For more information on Chaincode Labs’ 2018 Bitcoin residency program and to find out how to apply, see the company’s announcement and the program website.

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Scaling Bitcoin Releases This Year’s Program and a New Developer Bootcamp

October 13, 2017 Aaron van Wirdum 0

Today, Scaling Bitcoin, the international engineering conference focused on Bitcoin and blockchain research, released its program for the 2017 edition. The conference, to be held in Stanford, California, in the first weekend of November, will also i…

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Bitcoin Gold Is About to Trial an ASIC-Resistant Bitcoin Fork

October 11, 2017 Aaron van Wirdum 0

Bitcoin Gold Is About to Trial an ASIC-Resistant Bitcoin Fork

It’s forking season.

After Bitcoin Cash (Bcash) forked from the Bitcoin blockchain to create a new cryptocurrency (BCH), and ahead of the SegWit2X fork that may do the same thing, a third Bitcoin fork is in the making: Bitcoin Gold (Bgold; BTG). But where Bcash and SegWit2X are scaling-related forks — both mainly increase Bitcoin’s block size limit — Bgold wants to re-decentralize mining by implementing a new proof-of-work algorithm.

“What was born as decentralized is now centralized,” Bitcoin Gold contributor J. Alejandro Regojo told Bitcoin Magazine, referring to the current state of Bitcoin mining. “With this fork, we want to show how Bitcoin can be as ‘Satoshi’ as possible, as social as possible, and as decentralized as possible.”

Mining Centralization

Bitcoin Gold was initiated by Jack Liao, CEO of Hong Kong–based mining hardware producer LightningASIC, and was first announced in late August. The open project has been gaining traction and support in the wider cryptocurrency space since, with a dedicated Slack as a main hub for discussion and organization. Bgold is currently being developed by the pseudonymous developer “h4x3rotab” along with a small group of volunteers contributing to the project in other ways.

The attention Bgold has attracted is probably in part because anyone who owns bitcoin (BTC) on October 25th will receive the equivalent amount of BTG. While this model has been criticized, particularly because it presents a burden on service providers and users, it has also proven successful. With the launch of Bitcoin Cash in particular, users eagerly accepted their batch of “free money,” while exchanges, wallets and other service providers proved relatively willing to integrate the new coin.

Further, the Bgold team believes that this distribution method should also benefit Bitcoin over altcoins as it provides an extra incentive to hold BTC on particular dates.

“But the key goal that we are trying to achieve with this fork is to build a perpetually ASIC-resistant version of Bitcoin,” said Robert Kuhne, another Bitcoin Gold contributor, in explaining the purpose of the project to Bitcoin Magazine.

Bgold contributors like Regojo and Kuhne think that Bitcoin’s proof-of-work hashing algorithm was essentially broken by the introduction of specialized ASIC (application-specific integrated circuit) mining hardware. In the early years of Bitcoin’s existence, individual users were often also miners; this has since become concentrated into relatively centralized data centers operated by professionals.

“And we’re now in a situation where 65 percent of hash power comes from a country that doesn’t like Bitcoin,” Regojo noted, referring to China’s recent clamp down on cryptocurrencies.

An Uneven Playing Field

And while mining is centralized, ASIC production is even more centralized, the Bgold contributors pointed out. Only a handful of companies currently produce such specialized chips.

This means that anyone who wants to be a miner in any meaningful way is beholden to these companies, Kuhne argued.

“The way the monopoly manufacturer currently operates is abusive to its customers — individual miners — and the industry at large,” he said, referring to major Chinese ASIC producer Bitmain. “Manufacturers can produce ASICs at a tiny cost, but miners have to buy at a high price. This violates the one-CPU-one-vote ethos as described in the Bitcoin white paper, because while everyone can buy CPU at the same price, the same is not true for ASIC hardware.”

Regojo and Kuhne see this as a fundamental problem — not something that free market dynamics can realistically resolve. They suggest that the barrier of entry to the ASIC market to compete with existing manufacturers is fundamentally too high to allow for open competition.

“You can’t build a factory without approval from the government and banking system. So there are really only a handful of entities in the world that have total authority over who can and can’t manufacture ASIC machines. And all this could potentially get much worse if and when those institution really start feeling the disruption from Bitcoin, which hasn’t begun in earnest yet,” Kuhne said.

Bitcoin Gold

As opposed to the Bitcoin Cash and (especially) the upcoming SegWit2X forks, Bitcoin Gold very specifically does not make a claim to be the “real” Bitcoin. Instead, the Bgold project hopes it can prove a valuable exercise for Bitcoin; a sort of test case for a hard fork that Bitcoin itself may one day require.

Concretely, Bitcoin Gold is now implementing the Equihash proof-of-work algorithm. This is already used by Zcash and is relatively ASIC-resistant.

Full ASIC-resistance, however, is thought to be impossible: Any mining algorithm could be subject to specialized chips. Like Vertcoin, the Bgold community therefore plans to re-deploy a new proof-of-work algorithm hard fork if it is found out that ASIC-chips for Equihash are being produced. (This plan alone, of course, could be a deterrent for any potential ASIC-producer.)

For security, the project plans to implement strong replay protection to avoid loss of funds for unsuspecting or non-technical users. It will also adopt a new difficulty re-target algorithm to prevent the blockchain from stalling: Difficulty is re-adjusted at every block instead of once every two weeks.

While the coin is set to launch two weeks from now, the Bgold codebase is not yet fully developed and ready to be deployed. Implementation of the new proof-of-work algorithm and replay protection, as well as the new difficulty re-adjustment scheme, are yet to be finished.

Nor are all the details for the project even ironed out.

Early announcements indicated that Bitcoin Gold would have a closed launch and a presale of coins. A new batch of BTG was to be mined in the first week after the fork and subsequently distributed to designated investors, not unlike an ICO. Proceeds of this “ICO” were then to be used for development and other Bgold-related purposes.

However, as interest in the project grew, this idea became more controversial. Not everyone involved with Bitcoin Gold likes the idea of an additional founders reward — something Bcash, for example, did not have.

Kuhne addressed the issue by stating: “We have heard a lot of feedback from the community, so this proposal will be replaced with an updated and improved plan. But we will not completely rule out the possibility of a modest pre-mine to provide a basic level of funding for the project.”

Disclaimer: The author of this article holds BTC and will therefore also own BTG at launch.

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Gem Partners With Nordic Tech Giant Tieto and the CDC to Put Healthcare on the Blockchain

September 28, 2017 Aaron van Wirdum 0

Gem Parnters With Nordic Tech Giant Tieto and the CDC to Put Healthcare on the Blockchain

Enterprise blockchain provider Gem is forging new partnerships in the healthcare sector. First announced at the Distributed: Health 2017 conference in Nashville, Tennessee, earlier this week, the blockchain startup is teaming up with European technology service provider Tieto as well as partnering with the U.S. Centers for Disease Control and Prevention (CDC).

“We fundamentally believe that data should not be centralized; it should exist at the edges where it already lives. Gem is partnering with Tieto and the CDC to build fluid systems of bridges and tunnels that connect relevant data at the time it’s needed,” Gem founder and CEO Micah Winkelspecht told Bitcoin Magazine.


The growing interest in blockchain technology does not appear to be slowing down. As just about every industry is researching whether and how blockchains can help their operations, the healthcare sector is no exception. Distributed: Health, the world’s only healthcare-focused blockchain conference, welcomed over 700 attendees to Nashville this week.

Among the interested parties was Tieto, a major technology service provider in northern Europe, which typically works closely with several Scandinavian governments. The company provides software solutions for a range of public sector agencies, in domains like forestry, finance and education, as well as healthcare.

In Nashville, Gem and Tieto announced their new partnership in the exploration of how blockchain technology can benefit the tech giant. Emily Vaughn, head of accounts at Gem, and Maria Kumle, head of new offerings (Lifecare Solutions) at Tieto, presented a keynote address on Tuesday morning outlining the companies’ shared vision for the future of healthcare and how their partnership will build blockchain-based compliance solutions.

“Tieto has a pretty big vision for the future,” Winkelspecht told Bitcoin Magazine after the presentation. “They believe in a shift from a provider-centric data model to a more citizen-centric data model. They think citizens should really be in control of their own data, where companies can leverage and use that data, if the user consents.”

Gem’s main product, GemOS, is a data collaboration platform to be deployed on blockchains like Ethereum and Hyperledger, a software stack to bridge the gaps between these blockchains’ enterprise-level applications. For Tieto, GemOS will be configured to connect different data silos, specifically Finnish blood banks and DNA registers.

Winkelspecht said:

“If, say, a life insurer needs access to your health records and that data is stored in 10 different locations, that insurer first needs to know what these locations are. Then it needs to demonstrate to all these locations that it has the rights to access this. And it should be able to pull them all down, to have availability to the data.”

Because this is still a very bureaucratic, slow and expensive process, Gem and Tieto believe they can streamline the localization and authorization of this data. While the different silos will remain siloed — the blood bank records and DNA registers won’t be stored on any blockchain — GemOS should provide the bridge to connect the relevant data where needed.


Prior to the conference, Gem also struck a recent deal with the CDC, the United States federal agency tasked with preventing the spread of disease.

The CDC is particularly interested in finding solutions to better manage population health data and, more specifically, data relevant for disaster response. This type of data is usually fed through several intermediaries, such as different local government bodies. And because this is still very much a manual process, getting the right information to the right departments can take weeks or even longer. This current level of inefficiency is of particular concern in emergency situations where time is of the essence.

On top of further automating their processes, the CDC thinks that blockchain technology may offer additional solutions. It has therefore already put together a 27-person blockchain development team and is also partnering with different blockchain providers, including Microsoft and IBM, in addition to Gem.

“The CDC wants to build a blockchain-based early-detection warning system for population health and other topics that they care about,” Winkelspecht explained. “Once again, we won’t put actual data on the blockchain, but what we’re trying to do is paint a clear, comprehensive picture of all the data that is available, with a validity check, a timestamp and a proof.”

These records should then be instantly available to other relevant parties in the disaster relief efforts, like doctors or pharmacies. Such real-time data-sharing solutions among parties could significantly benefit CDC’s mission, especially when it comes to contagious diseases.

Both the Tieto and CDC projects are still in early development phases. It could take another year before the projects are up and running.

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The Curious Case of Bitcoin’s “Moby Dick” Spam and the Miners That Confirmed It

September 27, 2017 Aaron van Wirdum 0

moby dick spam.jpg

The scaling debate has dominated the Bitcoin space for well over two years now. As a central issue, Bitcoin’s one-megabyte block size limit was often insufficient to include all transactions on the network. This ultimately led to the replacement of this block size limit for a block weight limit through Segregated Witness, allowing for up to four megabytes of transaction data. And a group of Bitcoin companies plans to deploy a hard fork to double this by November.

But there is reason to believe the “crisis” may have been fabricated, at least partly. A recent analysis by “LaurentMT,” the developer of blockchain analytics tool OXT, in cooperation with Antoine Le Calvez, creator of Bitcoin statistics resource, shows that the Bitcoin network has had to deal with a load of spam transactions throughout the past two years. Now, in a three-part blog post series dubbing the spam attacks “Moby Dick,” their findings suggest that several major Bitcoin mining pools may have had a hand in this.

“Six or seven pools have played a major role in stuffing blocks with spam transactions,” LaurentMT said. “And charts display what looks like a coordination between these pools.”

The Spam Situation

The very concept of “spam” in the context of Bitcoin is sometimes disputed. Differentiating between “good” and “bad” transactions can be controversial on a network designed for permissionlessness innovation and censorship-resistant payments.

But there is little doubt that certain transactions serve no other purpose than to stuff the Bitcoin network and blockchain. LaurentMT and Le Calvez more specifically define spam as transactions that send lots of tiny fractions of bitcoins to lots of different outputs (“addresses”). These kinds of transactions can’t feasibly have been used to make actual payments, while they do present a significant burden on the Bitcoin network: all nodes need to receive, validate, transmit and (at least temporarily) store all this data.

The analysts found that the Bitcoin network has seen many transactions that fit this category: almost three gigabytes worth of data within a two-year span, adding up to more than 2 percent of the total size of the blockchain, or the equivalent of about a month’s worth of normal Bitcoin use.

“We found that there were four waves of ‘fan-out transactions’ during summer 2015,” LaurentMT told Bitcoin Magazine, referring to the transactions that create lots of outputs. “We think that the first two waves were spamming users and services. The third and fourth waves instead mostly sent the fractions of bitcoins to addresses controlled by the attackers themselves.”

These four waves of spam have been relatively easy to notice, as sudden bursts of transactions clogged up the Bitcoin network for brief periods of time. In some cases these spam attacks were even announced as “stress tests” or “bitcoin giveaways.”

What’s more interesting about LaurentMT and Le Calvez’s analysis is that the two focused on the second half of the puzzle. Almost all the fractions of bitcoins that were sent to all these different addresses have slowly been re-spent back into circulation since. These “fan-in” transactions were not as obvious as the initial waves of spam — but were similarly burdensome.

And, LaurentMT explained, blockchain analysis suggests that most of this spam can be tracked down to one or two entities:

“We’ve identified two wallets that seem to have played a central role in the attacks. They’ve funded long chains of fan-out transactions during summer 2015, and they later aggregated the dust outputs.”

The analysts also suggest that the perpetrator(s) of the spam may have been customers of the Canadian exchange QuadrigaCX. But that’s where their analysis stops.

The Mining Pools

Perhaps what is more interesting is who used this spam to fill up Bitcoin blocks: Bitcoin mining pools.

The spam outputs, generated by the first four waves of fan-out transactions, had been starting to move since autumn of 2015 — sort of. Whoever controlled these addresses had been broadcasting transactions to spend these outputs over the network. However, for a long time, miners did not include these “spam broadcasts” in their blocks; the transactions were ignored.

Up until the second half of 2016, that is. At a very specific point in time, a group of seven mining pools started to suddenly accept these spam broadcasts and include them in the blocks they mined: 1-Hash, Antpool, BitClub Network,, HaoBTC, KanoCKPool and ViaBTC.

“So, either these seven pools had an ‘aha moment,’ and suddenly discovered that Bitcoin is about censorship resistance. Or, they had another motivation to fill up blocks with these transactions — perhaps related to the block size debate,” LaurentMT suggested.

For more clues, LaurentMT and Le Calvez looked for notable events that happened around the time of the mining pools’ sudden change of heart. In their research, they did find some correlation with “strange” occurrences. The first is an open letter from HaoBTC (now rebranded as Bixin) to the Bitcoin Core development team. The second was a rumor about a group of Chinese pools planning to end their cooperation with Bitcoin Core: the Terminator Plan.

Of course, something notable happens in Bitcoin just about every week. These events may well be coincidences and, therefore, there could be a very different explanation for the mining pools’ behavior, LaurentMT acknowledged:

“An alternative explanation could be that the different mining pools adopted new mining policies for completely different reasons. I tend to think political motivations are more likely … but that’s just a personal opinion.”

Bitcoin Magazine reached out to the seven mining pools in question. The only mining pool willing to comment on the issue was KanoCKPool, which denied being involved with any sort of manipulation or coordination, stating it just confirms “any and all transactions available.”

For a full analysis of the “Moby Dick” spam, read LaurentMT and Le Calvez’s three-part blog post series or watch Le Calvez’s presentation at Breaking Bitcoin in Paris earlier this month.

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SegWit2X and the Case for Strong Replay Protection (And Why It’s Controversial)

September 22, 2017 Aaron van Wirdum 0


Come November, the remaining signatories of the “New York Agreement” (NYA) plan to deploy the “SegWit2X” hard fork to double Bitcoin’s block weight limit, allowing for up to 8 megabytes of block space. Since not everyone supports this hard fork, this could well “split” the Bitcoin network into two incompatible blockchains and currencies, not unlike Bitcoin and Bitcoin Cash (Bcash) did two months ago.

But this NYA hard fork is controversial and not only because it lacks consensus. It’s also controversial because of design choices made by the development team behind BTC1, the software client associated with the New York Agreement. Perhaps most importantly, this development team, led by Bloq CEO Jeff Garzik, has so far refused to implement replay protection, a measure that Bcash did take. Partly for this reason, at least one NYA signatory — Wayniloans — has backed out of the agreement.

So what is replay protection, why should BTC1 implement it … and why doesn’t it?

What Is Replay Protection? (And What Are Replay Attacks?)

Bitcoin could see another “split” by November. (It’s arguably more accurate to consider the “splitting” nodes and miners as an entirely new cryptocurrency with a new blockchain and token — not an actual split of Bitcoin itself.) For the purpose of this article, we’ll refer to the blockchain and currency that follows the current Bitcoin protocol as “Legacy Bitcoin” and “BTC.” The blockchain and currency that follows the New York Agreement hard fork is referred to as “SegWit2X” and “B2X.”

If this split happens, the two blockchains will be identical. All past transactions and (therefore) “balances” are copied from the Legacy Bitcoin blockchain onto the SegWit2X blockchain. Everyone who owns BTC will own a corresponding amount of B2X.

Without replay protection, new transactions will be equally valid on both chains as well. This means that these transactions can be copied or “replayed,” from one chain to the other — in other words, for them to happen on both. This is called a “replay attack.”

So, let’s say Alice holds BTC at the time of split, which means she also owns B2X after the split. Then, after the split, she wants to send BTC to Bob. So, she creates a transaction that spends BTC from one of her Legacy Bitcoin addresses to one of Bob’s Legacy Bitcoin addresses. She then transmits this transaction over the Legacy Bitcoin network for a Legacy Bitcoin miner to pick it up and include in a Legacy Bitcoin block. The payment is confirmed; all is good.

But this very same transaction is perfectly valid on the SegWit2X blockchain. Anyone — including Bob — can take Alice’s Legacy Bitcoin transaction and also transmit it over the SegWit2X network for a miner to include in a SegWit2X block. (This can even happen by accident quite easily.) If this payment is also confirmed, Alice has inadvertently sent Bob not only BTC but also an equal amount of B2X.

And, of course, all of this is true in reverse as well. If Alice sends B2X to Bob, she might accidentally send him BTC as well. A lack of replay protection, therefore, is a problem for users of both chains. No one wants to accidentally send any money — not even if it was “free money.”

Technically, there are ways to “split” coins on both chains to ensure they can only be spent on one chain. This would, for example, require newly mined coins to be mixed into a transaction. Tiime-locks can also offer solutions. But this takes effort and is not easy, especially for average users — not to mention that many average users may not even know what’s going on in the first place.

To avoid this kind of hassle, at least one side of the split could add a protocol rule to ensure that new transactions are valid on one chain but not the other. This is called replay protection.

Why Should BTC1 Implement Replay Protection? (And Why Not Bitcoin Core?)

In case of a split, at least one side must implement replay protection. But many — Bitcoin Core developers and others — believe there’s only one viable option. It’s the splitting party — in this case BTC1 — that should do it.

There are several arguments for this.

First of all, it makes the most sense for BTC1 to implement replay protection because that requires the least effort. BTC1 is a new client that’s already implementing new protocol rules anyway, and it’s not very widely deployed yet. It would be relatively easy for BTC1 to include replay protection.

Meanwhile, it would not be sufficient for Bitcoin Core to implement replay protection on its own. While it is dominant, and even considered by some to be the protocol-defining reference implementation, Bitcoin Core is not the only Bitcoin implementation on the network. Bitcoin Knots, Bcoin, Libbitcoin and other alternative clients would all have to implement replay protection, too. (And that’s not even taking non-full node clients into account.)

But even more importantly, the reality of the current situation is that all deployed Bitcoin nodes do not have replay protection implemented. And logically, they can’t: Some of these nodes even predate the New York Agreement. So even if Bitcoin Core and other implementations were to implement replay protection in new releases of their software, it wouldn’t suffice. All users must then also update to this new version within about two months: a very short period of time for a network-wide upgrade.

If only some of the nodes on the network upgrade to these new releases, Bitcoin could actually split in three: Legacy Bitcoin, SegWit2X and “Replay Protected Bitcoin.” Needless to say, this three-way split would probably make the problem worse — not better.

Lastly, there is a bit of a philosophical argument. Anyone who wants to adopt new protocol rules, so the argument goes, has the responsibility to split off as safely as possible. This responsibility should not fall on those who want to keep using the existing protocol: They should be free to keep using the  protocol as-is.

Many developers — including RSK founder Sergio Lerner who drafted the SegWit2Mb proposal on which SegWit2X is based — have argued that BTC1 should implement replay protection. In fact, many developers think that any hard fork, even a hard fork that appears entirely uncontroversial, should implement replay protection.

But so far, the BTC1 development team will only consider optional replay protection.

What’s Wrong With Optional Replay Protection?

Implementing optional replay protection, as proposed by former Bitcoin developer Gavin Andresen, for example, is currently on the table for BTC1.

In short, this type of optional replay protection would make certain specially crafted (“OP_RETURN”) Legacy Bitcoin transactions invalid on the SegWit2X chain. Anyone who’d want to split their coins could spend their BTC with such a transaction. These transactions should then confirm on the Legacy Bitcoin blockchain but not on the SegWit2X chain. This effectively splits the coins into different addresses (“outputs”) on both chains.

Such optional replay protection is probably better than nothing at all, but it’s still not a definitive solution.

One problem is that the Legacy Bitcoin blockchain would have to include all these OP_RETURN transactions. This would probably result in more transactions on the network and would require extra data for each transaction. All this data must be transmitted, verified and (at least temporarily) stored by all Legacy Bitcoin nodes. It presents a burden to the Legacy Bitcoin network.

But more importantly, it would probably still not be very easy to utilize this option. It might suffice for professional users — exchanges, wallet providers and other service providers — as well as tech-savvy individual users. But these are generally also the types of users that would be able to split their coins even without replay protection. Average users, if they are even aware of what’s going on, would probably find it much more difficult to utilize optional replay protection.

Optional replay protection, therefore, offers help to those who need it least and does little for those who need it most.

Does the NYA Preclude Replay Protection?

While it’s unclear what was (or is) discussed behind closed doors, the New York Agreement seems to be a very minimal agreement. Published on May 23, 2017, it really only consists of two concrete points:

  • Activate Segregated Witness at an 80 percent threshold, signaling at bit 4, and

  • Activate a 2 MB hard fork within six months.

With the first point completed through BIP91, the only remaining point is a hard fork to 2 megabytes before November 23. (This assumes that this hard fork wasn’t completed with the creation of Bitcoin Cash which is supported by a number of NYA signatories.)

Notably, a lot of details are not filled in. For example, the agreement does not even state that signatories must specifically run the BTC1 software: Any software implementation that implements a hard fork to 2 megabytes might do. This could even include a software implementation that implements replay protection. And, of course, nothing in the NYA stops BTC1 from implementing replay protection; some signatories may have even expected it.

Why Won’t BTC1 Implement Replay Protection?

There are really several reasons why BTC1 — both stated and speculated — might not want to add replay protection.

The first reason is that replay protection would require simplified payment verification (SPV) wallets and some other thin clients to upgrade in order to send and receive transactions on SegWit2X. Replay protection would, therefore, in the words of BTC1 developer Jeff Garzik, “break” SPV wallets; they wouldn’t be compatible with SegWit2X until upgraded.

This framing and choice of words is disputed. If SegWit2X were to implement replay protection (and if SPV wallets don’t upgrade), these wallets could still send and receive transactions on Legacy Bitcoin perfectly fine. On top of that, they wouldn’t accidentally spend B2X when they don’t mean to.

Meanwhile, if the SegWit2X chain does not implement replay protection (and if SPV-wallets don’t upgrade), users may not be sure if their wallet is receiving or sending BTC transactions or B2X transactions or both. They also may not be sure if the balance in their wallet is a BTC balance or a B2X balance or both. And if hash power moves from one chain to another over time, these wallets could even switch from displaying BTC balances to B2X balances or the other way round without users knowing. (This problem could be solved, to some extent, through another workaround, but this is not yet implemented in either.)

Indeed, not implementing replay protection on SegWit2X could arguably “break” SPV wallets much worse.

The only (plausible) scenario where implementing replay protection would perhaps not break SPV wallets much worse is if there is no Legacy Bitcoin to speak of. Indeed, the New York Agreement very specifically intends to “upgrade” Bitcoin, rather than split off into a new coin as Bcash did. And based on miner signaling and statements of intent by several big Bitcoin companies, some NYA signatories claim that Legacy Bitcoin will not be able to survive at all.

Implementing replay protection is, therefore, sometimes considered an admission that SegWit2X will split off from (Legacy) Bitcoin into something new and will not be considered the upgraded version of Bitcoin.

But the assumption that Legacy Bitcoin won’t be able survive is a big one. In reality, miner signaling is effectively meaningless, while Bitcoin Core — the dominant Bitcoin implementation — will not adopt the hard fork. There is also a significant list of companies that have not stated that they support the hard fork, including two top-10 mining pools. Similarly, it’s not clear if many (individual) users will support SegWit2X either. The implementation of wipe-out protection (another safety measure) also suggests that even BTC1 developers aren’t so sure that there will only be one chain.

And perhaps even more importantly, it’s not clear that replay protection would affect any of this. If miners, developers, companies and users are to consider SegWit2X an upgrade of Bitcoin, they will probably do so with or without replay protection.

This is why it has also been suggested that BTC1 is rejecting replay protection for the specific purpose of being as disruptive as possible. If the Legacy Bitcoin chain is effectively made unusable, SegWit2X might stand the best chance of being recognized as “Bitcoin.”

For more information and debate on replay protection, also see the the relevant threads on the SegWit2X mailing list.

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