• A hard fork occurs when one cryptocurrency (like bitcoin) breaks off to form a new currency (like bitcoin cash).
  • Hard forks take place when the community wants to make a significant upgrade or disagrees on how to move forward.
  • Examples include bitcoin cash, ethereum classic, and bitcoin gold.

Cryptocurrency Hard Forks: Explained

A hard fork is when one cryptocurrency spins off to create another. Think of it like a train track splitting in two. The new coin (and its blockchain) takes a new direction from the old, but they share the same history. It’s a simple fork in the road.

bitcoin hard fork diagram

Let’s take the example of Bitcoin Cash, which is a hard fork of Bitcoin.

In 2017, the Bitcoin community disagreed on how to make improvements to the network. One group wanted to stay true to the old rules and “protocol.” Another group wanted to make drastic changes to how transactions were processed.

Unable to reach an agreement, the second group “forked” off to create a new blockchain. Bitcoin Cash was born.

Bitcoin Cash shares the same blockchain as Bitcoin right up until the moment it forked. From that point onwards, Bitcoin Cash took its own path with its own rules.

bitcoin cash hard fork
Image credit

Bitcoin has forked countless times as the community seeks to improve the technology or disagrees on how to move forward. These forks are not always successful.

How Hard Forks Work

Every blockchain enterprise has its own rules. Those rules dictate how the system works. How large is each block? What rewards do miners get? How are fees calculated? And so forth. One day, the community disagrees on some tidbit, such as whether new code should be introduced or whether participating miners should receive a bonus.

A successful fork is where most of your users agree, collectively make the changes, and move over to the new blockchain. A contentious or experimental fork is where your users split. Some might stick with the present blockchain, some may migrate to the new blockchain, and some use both. Soon you have two versions of your cryptocurrency with different rules.

A failed fork occurs when too few users leap to the new blockchain. That new cryptocurrency quickly becomes worthless.

Hard forks also happen in the following cases:

  • To fix important security risks found in older versions – It took the dollar more than 300 variations to become today’s counterfeit-resilient currency. Blockchain developers aim to make their blockchains 100% breach-free.
  • To add new functionality – Windows 10 is enormously different from its very first version. Blockchain developers upgrade their versions from year to year, adding functions for improvement.
  • To reverse transactions – If website developers suspected a security breach, they could block the previous fork, declaring all previous transactions non-existent. Their new fork would herald a new start.

Hard Forks Can Mean Free Money

The new blockchain is a replica of the old, so all transactions barreling through blockchain A are replicated on blockchain B. If you’ve joined blockchain B, you receive those coins as well as new ones that are mined on your blockchain. Those new coins are known as an airdrop.

crypto airdrops falling

Image credit

When Bitcoin Cash forked, everyone holding bitcoin received the same number of bitcoin cash tokens, essentially for free.

There is a catch, though. You’ll want a secure, private wallet that supports the airdropped coins on the new fork. If you keep your cryptocurrency on an exchange like Coinbase or Binance, the exchange may keep them.

You’ll also want to check whether the forked coin has a future. The unfortunate truth is that most coins fail. Look at the reputation of the fork developers; what are their reviews? Also, see whether credible blockchain services have inspected and credited the open source code of this new coin.

Are Hard Forks a Good Thing?

Some people in the crypto community oppose forks fearing that the new coin will devalue their old. However, a successful fork usually means good news for traders.

When a new fork is announced, we often see a flurry of traders rushing to buy the coin hoping to get free airdrops. That naturally increases the price.

It’s true that the forked coins often become worthless, but some are successful and ultimately valuable, such as bitcoin cash. You’ll often see a profit from a successful airdrop.

Sometimes the hard fork is widely opposed by the majority of people. When that happens, it can strengthen support for the original coin, sending the price up.

Hard Fork Example: Bitcoin Cash

bitcoin cash logo

In August 2017, a group of Bitcoin stakeholders including investors, entrepreneurs, developers, and China-based miners quarreled over the size of the Bitcoin block. Some wanted to keep the one megabyte (MB) limit coded into Bitcoin by Satoshi Nakamoto himself. Others wanted to increase the size to two MB while other stakeholders fretted it should exceed 9,000!

The team eventually split. Bitcoin loyalists adhered to the old protocol, while critics created a new coin called bitcoin cash.

Bitcoin cash never became as popular as the original bitcoin. In December 2017, bitcoin cash was worth $4,355.62. August, 2018, bitcoin cash sold for $519.12. The research firm Chainanalysis noted that in May 2018, the 17 largest payment processing services processed bitcoin cash payments worth US$3.7 million, down from US$10.5 million two months before

To date, Bitcoin’s hard fork iterations include the following:

  • Bitcoin Platinum (BTP). December 1, 2017. A scam, invented by a South Korean teenager in an attempt to kill the price of bitcoin and profit by betting against it.
  • Super Bitcoin (SBTC). December 15, 2017. Among other changes, Super Bitcoin included smart contract functionality, taking a leaf out of the Ethereum blockchain.
  • Bitcoin God (GOD). December 25 2017. Chandler Guo proclaimed Bitcoin God a Christmas gift to bitcoin holders. Most called it bizarre
  • Bitcoin Uranium (BUM). December 31, 2017. BUM was an attempt to democratize Bitcoin, which critics said had become dominated by a small group of entities over-exerting their power over miners. BUM was created as Satoshi’s original vision. It bummed.
  • Bitcoin Cash Plus (BCP). January 2, 2018. Promised “low fees and reliable confirmations”. It flunked almost from the start.

Bitcoin also spawned Bitcoin Diamond (BCD), Bitcoin Gold (BTG), Bitcoin Atom (BCA), Bitcoin Core (BTX), Bitcoin Private (BTCP or ZCL) and Segwit, among others.

Segwit was a soft fork which is quite a different creature.

What is a Soft Fork?

Hard forks are unique in that the changes are incompatible with the previous protocol. Soft forks are different because the software or protocol changes are compatible with the previous versions.

Think of a hard fork being the difference between PlayStation 3 and PlayStation 4. You can’t play PS3 games on PS4 and you can’t play PS4 games on PS3.

A soft fork, on the other hand, is more like Microsoft Excel. You can use MS Excel 2015, even with MS Excel 2005 running in the background. The upgraded version is compatible with the old. At the same time, the updates in the newer version don’t appear in the old. MS Excel 2015 shows features that don’t appear in MS Excel 2005. The new soft fork has additional – or different – features to its older version.

In other words, soft forks have backward compatibility. The new chain contains the previous rules with additions, while the previous blockchain continues unchanged.

segwit soft fork diagram

Image credit: Reddit user u/k06a

As you can see in the diagram, the SegWit fork of Bitcoin is a “soft fork.” It doesn’t create its own blockchain. It simply upgrades and continues the previous chain. In contrast, the hard forks, like Bitcoin Cash and Bitcoin Gold actively split off.

With a hard fork, you need 90 to 95% of the stakeholders, or nodes, to accept your changes for the system to succeed. For a soft fork, you only need a majority of miners to upgrade and agree on the new version.

Soft Fork Example: The SegWit Solution

One of Bitcoin’s greatest frustrations is its slowness. Ten transactions take about a second to slip through compared to Visa’s 5,000-8,000 transactions per second. This is called the “scalability” problem.

In October 2016, Pieter Wuille, a Bitcoin Core developer, tried to treat this problem by modifying the appearance of the Bitcoin block.

Bitcoin blocks have two sections:

  1. The header with its cryptographic data.
  2. The body with transactions and sender/receiver data.

The bulkier the block, the slower traffic.

Wuille divided transactions from sender and receiver data. He gave each their own blocks, creating, in effect, a freeway where bitcoin transactions zoomed through, while so-called witness boxes (SegWit, short for Segregated Witnesses) with scripts and signatures used the parallel lane.

SegWit is called a “soft fork” since it was compatible with Bitcoin’s old code. All Bitcoin needed was 95% of its miners to accept the changes, which happened in less than a year. The platform didn’t need a separate blockchain and currency to make alterations work.

Update:

Critics complained that Segwit fell short of solving Bitcoin’s congestion problems and that the platform needed major changes to decongest its platform. Dissension led to the string of hard forks like the previously mentioned Bitcoin Cash (BCH). In 2017, Bitcoin developers also promoted hard fork SegWit 2x to magnify blocks from 1 MB to 2 MB. That fork died a week before it was scheduled to occur.

Bottom Line

A hard fork:

  • Results in two new blockchains, both of which share the same past.
  • Changes a fundamental aspect of the blockchain or the rules that govern it.
  • Is not compatible with previous versions.

A soft fork:

  • Does not create a new coin or split the blockchain.
  • Upgrades the system with new features that are compatible with the old version.

It’s as simple as that.

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We’ve heard it hundreds of times. Blockchain is Web 3.0 or Geekdom’s latest marvel. Entrepreneurs, or business owners, who capitalize on this technology when young make it rich. Innovators like Ripple turned a $10,000 investment into $1.5 million in five years. Binance, only a year old, has a market cap of $840.8 million, according to Coinmarketcap. So it’s understandable that you’d speculate about launching your own business blockchain. You may not want to innovate anything, but, hey, blockchain’s said to be the next Revolution. Blockchain fanatics say it’s a core differentiator and value driver, leading you, if you have a business, to quite likely think maybe you should jump on board.

Should you?

Brian Winker’s take on blockchain for business

Sometime last year, I interviewed Brian Winkers, founder of blockchain money automation company bitlov.com that won first place in the 2015 StartUp Chile! Competition.

Winkers himself is an open-source developer and Bitcoin analyst who has been playing around with crypto projects since 2012 and has helped small and medium-sized businesses get on or, rather, more often, off the blockchain.

For Winkers, blockchain for small business is a bonkers idea, largely because of Bitcoin. Bitcoin’s platform has problems with scalability: The platform is slow – around ten transactions per second compared to Visa’s 5,000 to 8,000 transactions in the same time span. The ledger became congested. The company itself struggles with internal squabbling.

Truth is Bitcoin is competing with more scalable and less problematic platforms like Ethereum and IOTA, so businesses can profit from blockchain more than was possible, say, ten years ago.

The problem is the expense.

Blockchain expense

Blockchain technology is free if you want to do all the work. The problem is recruiting a blockchain developer, and that’s where the trouble starts. As of 2018, a decent blockchain developer costs anywhere from $150,000 to $200,000 at the very least. Forget the fly-by-night freelancer from a platform like Elance, Guru or the like. Actually employing someone from such a platform would likely cost you more, since you may have to pay for errors. Any coding error or slight mishap means the ledger needs to be dismantled and rebuilt from scratch, aside from which technological changes occur so rapidly that top blockchain developers regularly familiarize themselves with updates.

Want a top developer? Expect to pay $250,000-$450,000 for a whiz, or triple that for a world-class specialist, according to Pavel Supronov on Medium. You think blockchain saves you money? According to John Levine, crypto consultant, author, and speaker, blockchain is the most expensive database ever invented.

Is your blockchain for innovation?

To get some ROI from your blockchain investment, you need some really BIG idea that’s stupendously different than competitors and that delights hordes of people. (Think of a Ripple or Binance).  Such a feat, according to Winkers, is performed by only two out of every hundred ICOs or startups.

In all my years,” Winkers told me, “I’ve only found one ICO that makes sense, and that’s the one I’m with right now. A Russian company called Visor looking to create a payment coin. I’m providing some technical guidance, more on the architecture side. I think they have a good team that understands the need to meet the underlying business needs. It’s not about them having a big payday.”

Winkers added:

I regularly tell businesses not to proceed with Bitcoin, but to focus on more conventional solutions. I try to help them customize their business, figure out what they can do.  Unfortunately, most people who approach me are dazzled by Bitcoin and the ledger. They don’t understand it… but just about everyone’s doing it so they want on the bandwagon. Now if they’d have a wonderful remarkable useful idea that may be one thing, but they often emerge with impractical, unfeasible ‘solutions’, so it’s a waste of their time and money.

At the end of the day, if your mind is on blockchain for fame or money, Winkers doubts you’ll succeed. You’ll want to have a solid idea that makes sense and that lasts for decades.

Blockchain to save you money?

How about if you don’t want to innovate but are sold by the blockchain hype and want blockchain to expedite your business? Say, you’ve read reports like that by management consulting giant Accenture and McLagan who insisted that blockchain promises cost savings of 70 percent or more in finance areas? Or you read the 2014 EY report how blockchain-based businesses outpace competitors?

Well, blockchains have certain problems that you’d want to know about…

The National Institute of Standards and Technology (NIST) – a non-regulatory agency of the U.S. Department of Commerce – recently released a report for beginners to blockchain and business owners often tempted by new technology.

The report pointed out that blockchain can’t control users’ conduct.  The NIST also highlighted the misconception that blockchain is “trustless” – you need a great deal of trust in the technology, developers, and user cooperation for the blockchain to function. Further, users must manage their own private keys that, once lost, are harder to recover than usernames or passwords on centralized platforms.

Additionally, blockchains are massively inefficient. Set up a blockchain and you’ll need each and every user to archive, and constantly update, a complete history of all that’s happened on that blockchain. 

Finally, but not conclusively, blockchains also require a computational challenge to restrict the creation of new blocks. If it’s too easy, hackers could temporarily mobilize enough computing power to rewrite history; if it’s too hard, each new block will consume megawatts of electricity. And electricity for blockchain costs hundreds, if not thousands, of dollars.

On the other hand…

As we speak, blockchain improves all the time. More modern technologies produce decentralized platforms that have more bandwidth, are faster, more convenient, easier to program. IOTA, for example,  uses a “blockchain” that isn’t the traditional format but a new one called Tangle that knocks out the expense and time of mining. IOTA transactions are super-fast and process several transactions simultaneously.  Its structure perfectly suits the Internet of Things (IoT), where products and appliances like cars, home appliances and machinery “tangle”. Businesses on  “next generation” blockchains like IOTA report a smooth, fast and cheap experience that almost resembles that of the Web.

So to blockchain or not to blockchain?

A unanimous decision tree floating the Web may resolve your problem.

Ask yourself the following:

  1. If you need a database, are all the writers or participants on your team known and trusted? Is there anything you need to hide? Do you need to hire, or involve, trusted third parties? Do you need to control functionality? Are your transactions private? If your answers are a flat “no” to each of these questions, either stick to a standard database or use a public blockchain.
  2. Does more than one participant need to be able to update the data? Do you need to hire third-parties whom you’re unsure whether you can trust? Do you have any confidential data? Do you and all the updates on your team barely know one another or have some qualms of one or more users? If you answered “yes” to one or more of these questions, use a permissioned or hybrid blockchain.
  3. Does the data need to be kept private? Do you need to control who can make changes to the blockchain software? Do you have the money for blockchain programming and continuous maintenance and upgrades? Consider a private blockchain.
Do you even need Blockchain?

Even then Winkers would tell you to mull your decisions carefully. 

“I’ve always worked to make sure that small businesses aren’t taken advantage of by others in the technical fields,” he told me, “And that includes blockchain. For some it’s the right path, for others, it’s a costly diversion.”

“ICO companies that invest in blockchain have a 98% failure rate. That’s not the route,” Brian insisted, ”that I’d want to take.”

 

About three years ago, a so-called crypto-anarchist, deep into libertarianism, hired me to write a book that included content railing against government anti-money laundering regulations. As he saw it, there is essentially nothing wrong with financially supporting terrorist organizations,  smuggling drugs or other contraband items. (Hell, there was nothing wrong with terrorism to him; one man’s terrorist is another man’s freedom fighter). People can do what they want as long as they don’t harm others. Drugs and prostitutes (for instance) delight individuals. And, therefore, the government, which, by the way, does a lousy job of literally minding its own business should focus on “minding its own business”.

Five years later and knowing more on money laundering, I think large-scale smuggling and certainly funding terrorists may have more negative social and economic ramifications than my well-meaning friend opined. This is  partly because unrequited criminal laundering turns us into a criminal society – after all why work ethically when we can make far more money in illicit activities. Above all, successful money laundering means more drugs on the streets, more drug-related crime, more fraud, more corporate embezzling, and more terrorism, among a host of other social ills.

What  is money laundering?

money laundering

 

Money laundering, at its simplest, is the act of trying to make money that comes from nefarious Source A look like it comes from “clean” Source B. If caught, the perpetrator can’t use that money, since law enforcement would seize it. Source A involves funding ISIS, smuggling cocaine, engaging in corrupt political businesses, or benefiting from fraudulent business schemes, as examples.

If I were involved in any of these activities and would want to retain my stash, I’d be advised to go through the following three steps:

  1. Placement – Find a place to stash my money. If I wire the trove to my banks Capital One or Charles Schwab, they’d have to tell the government I’m suddenly depositing millions in checks. So I need to find a resilient hiding place.
  2. Layering – Money launderers can teach me all sort of schemes like wiring money between different accounts in different names in different countries, or purchasing high-value items (boats, houses, cars, diamonds) to change the form of my money. I can also change my money’s currency – and this is where cryptocurrency comes in. So, I can change my dirty dollars into Bitcoin and then again into Monero or Dash to better hide its source – now there’s a way to evade the cops!
  3. Integration – At this point, my money re-enters mainstream society as though it comes from a legitimate source. I’ve strategized in such a way that my startling fortune is innocuous and can slip under the radar.

The government’s response to money-laundering

Anti-money laundering regulations

In the United States, the Department of Justice, the State Department, the Federal Bureau of Investigation, the Internal Revenue Service and the Drug Enforcement Agency join forces in catching money-launderers like me. State and local police investigate cases under their jurisdiction. On the international stage (and when it comes to blockchain), organizations like the United Nations, the World Bank, the International Monetary Fund and the Financial Action Task Force on Money Laundering (FATF) send in their troops. The last has 33 member states and organizations, as of 2018.

Cops combine legislation with law enforcement.  In the United States, legislative acts include:

  • The Bank Secrecy Act (1970) – Financial institutions have to report all single transactions above $10,000 and multiple transactions totaling more than $10,000 to or from a single account in one day. When it comes to the blockchain industry, this includes money service businesses (MSB), too. Bankers who violate this rule can serve up to 10 years in prison.
  • The 1986 Money Laundering Control Act – Any aspect of money laundering is a crime punishable by fines or jail.
  • The 1994 Money Laundering Suppression Act – Banks have to establish their own money-laundering task forces to weed out suspicious activity in their institutions. When it comes to blockchain-based financial institutions, customer due diligence (CDD) rules are no different.

In truth, it’s a perpetual chase of cops vs. robbers, with the robbers mostly slipping through even as cops set the traps.

How do AML rules impact ICOs?

ICOs, also known as token sales, can fall foul of anti-money laundering regulations with their digital tokens.  While “utility tokens” that only give investors access to the startup’s features are ok,  it is the “security tokens” that may offer investors equity or some form of an investment return that are problematic.

This is where a growing number of ICOs interest themselves in Know Your Customer (KYC) and Anti-Money Laundering (AML) regulations for reasons that include the following:

  1. Establish credibility with banks – After all, banks don’t want to trip up with organizations like FinCen, a bureau of the U.S. Department of the Treasury, that snoops into whether financial institutions are adhering to KYC.
  2. Long-term legitimacy – It’s good for your bottom line. You don’t want the government to bust your booty as happened in 2014 with Mt. Gox, the largest Bitcoin exchange, after the US Department of Homeland Security (DHS) seized suspicious money from its U.S. subsidiary account.
  3. Improved public perception – You appear more legitimate. You’re more likely to interest investors. The Dutch Authority for the Financial Markets (AFM), for one, warns consumers to avoid ICOs:

“Due to their unregulated status and the anonymous nature of the transactions involved, ICOs are attractive for the laundering of money obtained by criminal means. .. Because of these risks, there is a strong possibility that investors will lose their entire investment.”

With your compliance to KYC/ AML rules, you prove the AFM wrong.

4. Expanded reach – You’re more likely to attract investors in countries with rigid KYC/AML regulations like US, UK and Canada.

5. Avoid Regulatory Fines – There have been cases of regulatory bodies fining or suffocating ICOs that smell suspicious. With the Mt. Gox case, more than 3,000 customers lost some, or all, of their investments. You really don’t want that happening to you! AML in practice?

Our most recent guide to all there’s to “KYC: A  Practical Guide for Blockchain Entrepreneur and Investor” gives you the overall picture.

Really, it reduces to three steps:

  • Identify and do background checks on depositors.
  • Report all suspicious activity. (For example, if a background check revealed that depositor A works in an oil rig, and he deposits $2,000 every two weeks, a series of ten $9,000 deposits over two weeks should worry you.)
  • Build an internal task-force to identify laundering clues.

The rest is up to you.

hand-coin

The process of ‘Know Your Customer’ (KYC) is simple. Say you want to invest in an ICO, you may be particularly anxious that no organizations or individuals connected with or funding criminals and terrorists share the platform with you. KYC also refers to parties involved in other anti-government activities like money-laundering, smuggling, or coming from countries under sanctions. Even if you don’t care, the government does.

There have been stories where funds have been frozen or confiscated while the government inspected the company’s transactions. In 2014 for instance, more than 3,000 customers lost some, or all, of their investments in Mt. Gox, the largest Bitcoin exchange, after the US Department of Homeland Security (DHS) seized money from its U.S. subsidiary account.

I assure you, most token buyers would rather go through the quasi-onerous motions of KYC than have their crypto booty confiscated!

In a similar way, if you’re thinking of running a cryptocurrency exchange, a cryptocurrency ATM, or an ICO, you’d like people who participate in your token sales and incoming funds to be “clean”. Either way, FinCen, a bureau of the U.S. Department of the Treasury, requires ICOs to adopt KYC regulations. Finally, if you’re a money service business (MSB), you’d certainly want KYC to be your rule since banks, large corporations, and public bodies are all KYC-crazy.

As a client, this is what KYC means

Most credible bitcoin exchanges like Bitstamp, Coinbase, or Kraken will ask you to do the following:

  1. Confirm your phone number You’ll enter a code the company sends to your mobile phone.
  2. Provide personal IDYou’ll likely need to attach one or more of the following: a scan of your ID or driver’s license, a recent utility bill, and/ or a copy of your birth certificate or passport. The types of required ID documents depend on the bitcoin exchange and on the amount you want to trade, with larger amounts requiring stricter verification.  

Expect a growing number of ICOs, particularly those that are MSBs, to ask you for some of those documents, too.

Most major platforms verify your identification within one to three hours. Slower businesses may take up to a week.

As a business owner, here’s what KYC means

The process is simple:

  1. Establish customer identity – Collect basic identity documents or data like the following: IP address, name and address validation, citizenship, birth date, a photo of government issued ID (Driver’s License, passport, ID card), Social Security number or Tax Identification, bank statement, recent utility bill.
  2. Understand the nature of the customer’s activities (to satisfy yourself that the source of their funds is legitimate) – Check that they’re allowed to take part in a token sale (e.g., they are not on a sanctions list). IdentityMind Global, a service that offers risk management and anti-fraud services for e-commerce platforms, deals with this problem by comparing a selfie of the individual to the picture in the government issued ID.
  3. Monitor the customer’s activities – As of January 1, 2017, The New York Department of Financial Services (NYDFS) required an ongoing monitoring program that includes checking that the client’s financial transactions and accounts match their risk profile.

Some concerns are that individuals from sanctioned countries could hide their location and buy tokens from US companies. IdentityMind prevents this by looking at the IP address and determining, first, if the prospective clients uses a proxy (and if so, which kind), and, second, if it employs the Tor network or a VPN. If either is used, the application is denied. When it comes to money laundering, IdentityMind imposes EDD for contributors over a certain dollar amount.

EDD: Advanced KYC

There are three tiers of due diligence:

  • Simplified Due Diligence (“SDD”) – Situations where the risk for money laundering or terrorist funding is low, and you only need a partial KYC.
  • Basic Customer Due Diligence (“CDD”) – Information obtained for all customers to verify the identity of a customer and assess the risks associated with that customer. Here’s where you’ll need the complete KYC.
  • Enhanced Due Diligence (“EDD”) – Additional information collected for higher-risk customers to avoid possible risks.

Since this sounds like a lot of work and you have enough on your plate, some ICOs, or blockchain companies, dispatch identifications to third-party KYC providers, who, in turn, send documents to call centers around the world where clerks review information. Other blockchain companies, like data marketplace Datum, seek more confidentiality for their clients and review the data themselves.

Dealing with upset customers

Admittedly, KYC frazzles some people’s moods. Crypto enthusiasts, for instance, tend to disagree with the government’s “interference” ideologically, on the grounds that cryptocurrency should be anonymous, or at least, pseudo-anonymous. Others find the KYC requirements irksome and intrusive.

To modify such customers, you may want to make your requirements clear ahead of time, show how KYC protects investors, and that even if they disagree – “Sorry, guy, but we need this information to comply with FinCen’s Know your Customer requirements.

After all, know thy client saves you and your customers oodles of stress and money.

 

SegWit, short for Segregated Witness, is a system that makes your Bitcoin transactions faster.

Why do we need SegWit?

Think of a single lane highway with 5,000 vehicles driving along smoothly. As traffic builds to 50,000 and more, that single lane becomes clogged forcing you to wait hours on end in congested traffic and maybe miss your appointment. That’s Bitcoin. It’s called the scalability problem, and it’s an issue that the smartest blockchain developers have been trying to find solutions to for years.

SegWit is the Bitcoin team’s solution.

The scalability problem

One of Bitcoin’s most aggravating issues is its lack of speed. Ten transactions take about a second on average to process. Compare that to payment companies like Visa that are able to process around 5,000 to 8,000 transactions per second.

Pay more and you can get yours to the front of the queue, but that makes Bitcoin an expensive and undemocratic system. Besides which, Bitcoin wants to make its platform as efficient and as whizzingly fast as the internet to retain its users and grow its appeal.

The SegWit solution

Bitcoin transactions are made up of blocks with each block able to absorb no more than 1MB of data.

The blocks come in two parts: a header and a body. The header stores a cryptographic hash of the previous block, along with a time signature and other data. The body stores the transactions, including sender data and receiver public keys, which shows you this is a legitimate transaction. Each part takes up room and increases the mass of the block. The signature part alone that is needed to validate the information takes up around 60 percent of its bulk.

In October 2016, Pieter Wuille, co-founder of Blockstream and a Bitcoin Core developer decided to hack of the signature part and put it in a separate block.

Model: Structure of Segregated Witness

This block, called the “witness” block is separate to Bitcoin’s original block. We now have more room in our core block to slip in more information.  The block becomes lighter, so Peter’s idea also helps Bitcoin transactions move more efficiently.

In essence, Bitcoin added a parallel lane to its highway to divert some of its traffic from Route A (call it that) to Route B. Route A has the blocks with sender and receiver data, while the new parallel lane contains the “witness” segment with the scripts and signatures.

Result? The highway is less congested. Your Bitcoin transactions slip through faster.

Other benefits

  • Node performance – The Bitcoin platform is less congested, so nodes can verify blocks, or transactions, faster.
  • Cheaper transactions – At one time, increased demand raised fees. Now, Bitcoin can reduce its fees.
  • Transaction malleability – Originally, the sender’s signature, or the transaction id (txid), was vulnerable to an intruder hacking and changing it and, thereby, hacking the transaction. By SegWit moving the signature from the transaction data to another “lane”, it protects your transaction data from being hacked. 
  • Linear scaling of signature hashing operations – For certain transactions, adding more data, expands the amount of time that each signature needs to be verified. Segwit resolves this by changing the calculation of the transaction hash for signatures so that each byte of a transaction only needs to be hashed no more than twice.
  • Increased security for multi-signature transactions – SegWit provides two different scripts; one to a single public key that is vulnerable to hacking (and therefore to payments being stolen) and another that directs payments to a script hash. This boosts security for multi-signature transactions.
  • Building on top – SegWit frees Bitcoin for the development of second layer protocols, like its lightning network. SegWit activation also boosted development work on other features such as MAST (which enables more complex bitcoin smart contracts), Schnorr signatures (which would enable another transaction capacity boost) and TumbleBit (an anonymous top-layer network).
  • Protects Lightning Network – SegWit is great for payment channels like the Lightning Network (LN), where a vulnerable signature originally prevented more people from using it to remit Bitcoin. 

Where is SegWit now?

In August 2017, Bitcoin finally integrated SegWit into its system. SegWit is called a “soft fork” which means it is compatible with Bitcoin’s old code, minimalizing the hassle to make SegWit work. A hard fork, in contrast, is a system that is so totally incompatible with the old that a separate blockchain and currency is needed to make it work. 

In SegWit’s case, all the system needed was 95 percent of Bitcoin miners to accept the changes, which happened in less than a year.

In 2017, Bitcoin came out with a controversial hard fork SegWit 2x which increased block sizes from 1 MB to 2 MB. Most of the crypto community resisted SegWit 2x due to its ambitious changes. Consequently, the hard fork was canceled only a week before it was scheduled to occur.

What are the main problems with SegWit?

For one, miners and mining pool operators dislike SegWit. Transactions that go through Lightning Network are in a separate channel (i.e., the parallel “line”), which means these transaction fees will not flow to miners.

Some Bitcoin services – like Bitcoin wallets – have been slow to support the SegWit changes. In February 2018, only 14% of Bitcoin transactions were made using SegWit Bitcoin. The numbers have improved since then, but the network is still in the woods.

Critics complain that SegWit doesn’t go far enough to solve the scalability problem. They maintain that only major changes to the Bitcoin platform and to the way Bitcoin handles transactions can decongest transaction flow.

Finally, SegWit has caused divisions in the bitcoin community leading to several hard forks, such as Bitcoin Cash (BCH).