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Blockchain, Explained

‘Blockchain, Resolved’

If you have been following banking, investing, or cryptocurrency over the concluding ten years, you may be familiar with “blockchain,” the record-keeping technology behind Bitcoin. And there’s a gifted chance that it only makes so much sense.

In trying to learn sundry about blockchain, you’ve probably encountered a definition like this: “blockchain is a class, decentralized, public ledger technology.”

If you’re struggling with that meaning, it’s likely because it uses four-syllable words and three undefined calls — not because you can’t understand blockchain. While the technology underpinning blockchain is a bit multifarious complicated than its name lets on, there are easier ways to break this concept down than that definition may suggest.

Why Is It Bellowed Blockchain?

Before we get into the weeds, let’s get one thing out of the way. If this technology is so complex, why phone call it “blockchain?”

At its most basic level, blockchain is literally just a set of blocks — only, not in the conventional sense of those words. When we say the in a nutshell a quarrels “block” and “chain” in this context, we are actually talking about digital poop (the “block”) stored in a public database (the “chain”).

Instead of being made of wood or cheap, “blocks” on the blockchain are made up of digital pieces of information. Specifically, they obtain three parts:

  1. Blocks store information about transactions, say the rendezvous, time, and dollar amount of your most recent purchase from Amazon

  2. Hampers store information about who is participating in transactions. A block for your burn up purchase from Amazon would record your name along with Amazon.com, Inc. A substitute alternatively of using your actual name, your purchase is recorded without any specifying information using a unique “digital signature,” sort of like a username.

  3. Obstructions store information that distinguishes them from other bricks. Much like you and I have names to distinguish us from one another, each chunk stores a unique code called a “hash” that allows us to break it apart from every other block. Let’s say you made your show off purchase on Amazon, but while it’s in transit, you decide you just can’t resist and be in want of a second one. Even though the details of your new transaction would look precisely identical to your earlier purchase, we can still tell the blocks into pieces because of their unique codes.

While the block in the example beyond is being used to store a single purchase from Amazon, the authenticity is a little different. A single block on the blockchain can actually store up to 1 MB of matter. Depending on the size of the transactions, that means a single block can establishment a few thousand transactions under one roof.

When a block stores new information it is added to the blockchain. Blockchain, as its name suggests, consists of multiple balks strung together. In order for a block to be added to the blockchain, however, four instruments must happen:

  1. A transaction must occur. Let’s continue with the norm of your impulsive Amazon purchase. After hastily clicking owing to multiple checkout prompts, you go against your better judgment and go-ahead a purchase.

  2. That transaction must be verified. After making that support, your transaction must be verified. With other public documents of information, like the Securities Exchange Commission, Wikipedia, or your regional library, there’s someone in charge of vetting new data entries. With blockchain, respect, that job is left up to a network of computers. These networks often consist of thousands (or in the action of Bitcoin, about 5 million) computers spread across the globe. When you muddle through your purchase from Amazon, that network of computers peasants to check that your transaction happened in the way you said it did. That is, they sustain the details of the purchase, including the transaction’s time, dollar amount, and become associated withs. (More on how this happens in a second.)

  3. That transaction must be stored in a blot out. After your transaction has been verified as accurate, it gets the fresh light. The transaction’s dollar amount, your digital signature, and Amazon’s digital signature are all amassed in a block. There, the transaction will likely join hundreds, or thousands, of others predilection it.

  4. That block must be given a hash. Not unlike an angel pocketing its wings, once all of a block’s transactions have been verified, it must be fact a unique, identifying code called a hash. The block is also inclined the hash of the most recent block added to the blockchain. Once hashed, the stumbling-block can be added to the blockchain.

When that new block is added to the blockchain, it grows publicly available for anyone to view — even you. If you take a look at Bitcoin’s blockchain, you desire see that you have access to transaction data, along with data about when (“Time”), where (“Height”), and by who (“Relayed By”) the clog was added to the blockchain.

Where Is the Blockchain Stored?

Anyone can view the capacities of the blockchain, but users can also opt to connect their computers to the blockchain network. In doing so, their computer receives a copy of the blockchain that is updated automatically whenever a new deterrent is added, sort of like a Facebook News Feed that animate updates whenever a new status is posted.

Each computer in the blockchain network has its own replica of the blockchain, which means that there are thousands, or in the case of Bitcoin, millions of photocopies of the same blockchain. Although each copy of the blockchain is identical, spreading that low-down across a network of computers makes the information more difficult to utilize. With blockchain, there isn’t a single, definitive account of events that can be used. Instead, a hacker would need to manipulate every copy of the blockchain on the network.

Looking past the Bitcoin blockchain, however, you will notice that you do not have access to identifying intelligence about the users making transactions. Although transactions on blockchain are not expressly anonymous, personal information about users is limited to their digital signature, or username.

This propagates an important question: if you cannot know who is adding blocks to the blockchain, how can you corporation blockchain or the network of computers upholding it?

Trust and Security on the Blockchain

Blockchain technology accounts for the cause clebres of security and trust in several ways. First, new blocks are always preserved linearly and chronologically. That is, they are always added to the “end” of the blockchain. If you lift a look at Bitcoin’s blockchain, you’ll see that each block has a position on the bind, called a “height.” At the time of writing, the most recent block’s culmination is 548,015, meaning it is the 548,015th block to be added to the blockchain.

After a hamper has been added to the end of the blockchain, it is very difficult to go back and alter the delights of the block. That’s because each block contains its own hash, along with the ruin of the block before it. Hash codes are created by a math function that drive backs digital information into a string of numbers and letters. If that poop is edited in any way, the hash code changes as well.

Here’s why that’s notable to security. Let’s say a hacker attempts to edit your transaction from Amazon so that you as a matter of fact have to pay for your purchase twice. As soon as they edit the dollar amount of your minutes, the block’s hash will change. The next block in the chain commitment still contain the old hash, and the hacker would need to update that hindrance in order to cover their tracks. However, doing so would alter that block’s hash. And the next, and so on.

In order to change a single hindrance, then, a hacker would need to change every single congest after it on the blockchain. Recalculating all those hashes would take an elephantine and improbable amount of computing power. In other words, once a plan b mask is added to the blockchain it becomes very difficult to edit and impossible to cut.

To address the issue of trust, blockchain networks have implemented evaluates for computers that want to join and add blocks to the chain. The tests, recruited “consensus models,” require users to “prove” themselves before they can participate in a blockchain network. One of the most non-private examples employed by Bitcoin is called “proof of work.”

In the proof of urge a exercise system, computers must “prove” that they have done “wield” by solving a complex computational math problem. If a computer solves one of these troubles, they become eligible to add a block to the blockchain. But the process of adding deterrents to the blockchain, what the cryptocurrency world calls “mining,” is not easy. In points, the odds of solving one of these problems on the Bitcoin network are about 1 in 7 trillion at the moment of writing. To solve complex math problems at those odds, computers requisite run programs that cost them significant amounts of power and force (read: money).

Proof of work does not make attacks by hackers outrageous, but it does make them somewhat useless. If a hacker wanted to complementary an attack on the blockchain, they would need to solve complex computational math problems at 1 in 7 trillion odds right-minded like everyone else. The cost of organizing such an attack command almost certainly outweigh the benefits.

Blockchain and Bitcoin

The goal of blockchain is to budget digital information to be recorded and distributed, but not edited. That concept can be straitening to wrap our heads around without seeing the technology in action, so let’s ingest a look how the earliest application of blockchain technology actually works.

Blockchain technology was ahead outlined in 1991 by Stuart Haber and W. Scott Stornetta, two researchers who stand in want to implement a system where document timestamps could not be tampered with. But it wasn’t until bordering on two decades later, with the launch of Bitcoin in January 2009,  that blockchain had its key real-world application.

The Bitcoin protocol is built on blockchain. In a research dossier introducing the digital currency, Bitcoin’s pseudonymous creator Satoshi Nakamoto referred to it as “a new electronic coin of the realm system that’s fully peer-to-peer, with no trusted third hop.”  

Here’s how it works.

You have all these people, all over the world, who have planned Bitcoin. According to a 2017 study by the Cambridge Centre for Alternative Banking, the number may be as many as 5.9 million. Let’s say one of those 5.9 million people lust afters to spend their Bitcoin on groceries. This is where the blockchain rush at in.

When it comes to printed money, the use of printed currency is regulated and clinched by a central authority, usually a bank or government — but Bitcoin is not controlled by anyone. In preference to, transactions made in Bitcoin are verified by a network of computers.

When one human being pays another for goods using Bitcoin, computers on the Bitcoin network hop to it to verify the transaction. In order to do so, users run a program on their computers and try to reveal a complex mathematical problem, called a “hash.” When a computer resolves the problem by “hashing” a block, its algorithmic work will have also affirmed the block’s transactions. The completed transaction is publicly recorded and stored as a outline on the blockchain, at which point it becomes unalterable. In the case of Bitcoin, and ton other blockchains, computers that successfully verify blocks are rewarded for their labor with cryptocurrency. (For a varied detailed explanation of verification, see: What is Bitcoin Mining?)

Although deals are publicly recorded on the blockchain, user data is not — or, at least not in full. In systematize to conduct transactions on the Bitcoin network, participants must run a program draw oned a “wallet.” Each wallet consists of two unique and distinct cryptographic vital: a public key and a private key. The public key is the location where transactions are deposited to and taciturn from. This is also the key that appears on the blockchain ledger as the purchaser’s digital signature.

Even if a user receives a payment in Bitcoins to their unconcealed key, they will not be able to withdraw them with the private counterpart. A owner’s public key is a shortened version of their private key, created through a intricate mathematical algorithm. However, due to the complexity of this equation, it is almost illogical to reverse the process and generate a private key from a public key. For this deduce, blockchain technology is considered confidential.

Public Keys and Private Tone ELI5: Explain it Like I’m 5

Here’s the ELI5 (“Explain it Like I’m 5”) interpretation. You can think of a public key as a school locker and the private key as the locker combination. Dominies, students, and even your crush can insert letters and notes through the opening in your locker. However, the only person that can be repaid the contents of the mailbox is the one that has the unique key. It should be noted, however, that while equip locker combinations are kept in the principal’s office, there is no central database that shrouds track of a blockchain network’s private keys. If a user misplaces their concealed key, they will lose access to their Bitcoin wallet, as was the what really happened with this man who made national headlines in December of 2017.

In the Bitcoin network, the blockchain is not at best shared and maintained by a public network of users — it is also agreed upon. When owners join the network, their connected computer receives a copy of the blockchain that is updated whenever a new hindrance of transactions is added. But what if, through human error or the efforts of a penny-a-liner, one user’s copy of the blockchain manipulated to be different from every other carbon copy of the blockchain?

The blockchain protocol discourages the existence of multiple blockchains utterly a process called “consensus.” In the presence of multiple, differing copies of the blockchain, the consensus politesse will adopt the longest chain available. More users on a blockchain denotes that blocks can be added to the end of the chain quicker. By that logic,  the blockchain of catalogue will always be the one that the most users trust. The consensus note is one of blockchain technology’s greatest strengths, but also allows for one of its greatest appetites.

Theoretically, it is possible for a hacker to take advantage of the majority rule in what is referred to as a 51% start. Here’s how it would happen. Let’s say that there are 5 million computers on the Bitcoin network, a Rabelaisian understatement for sure but an easy enough number to divide. In order to win a majority on the network, a hacker would need to control at least 2.5 million and one of those computers. In doing so,  an attacker or arrange of attackers could interfere with the process of recording new transactions. They could send a matter — and then reverse it, making it appear as though they still had the silver they just spent. This vulnerability, known as double-spending, is the digital tantamount of a perfect counterfeit and would enable users to spend their Bitcoins twice.  

Such an infect is extremely difficult to execute for a blockchain of Bitcoin’s scale, as it would be short of an attacker to gain control of millions of computers. When Bitcoin was win initially founded in 2009 and its users numbered in the dozens, it would have been weaker for an attacker to control a majority of computational power in the network.  This detailing characteristic of blockchain has been flagged as one weakness for fledgling cryptocurrencies.

Consumer fear of 51% attacks can actually limit monopolies from propriety on the blockchain. In “Digital Gold: Bitcoin and the Inside Story of the Misfits and Millionaires Frustrating to Reinvent Money,” New York Times journalist Nathaniel Popper annuls of how a group of users, called “Bitfury,” pooled thousands of high-powered computers together to achievement a competitive edge on the blockchain. Their goal was to mine as many blank outs as possible and earn bitcoin, which at the time were valued at generally $700 each.

By March 2014, however, Bitfury was positioned to go beyond 50% of the blockchain network’s total computational power. Instead of proceeding to increase its hold over the network, the group elected to self-regulate itself and stated never to go above 40%. Bitfury  knew that if they chose to on increasing their control over the network, bitcoin’s value liking fall as users sold off their coins in preparation for the possibility of a 51% storm. In other words, if users lose their faith in the blockchain network, the news on that network risks becoming completely worthless. Blockchain purchasers, then, can only increase their computational power to a point beforehand they begin to lose money. 

Uses of Blockchain

Blocks on the blockchain stow away data about monetary transactions — we’ve got that out of the way. But it turns out that blockchain is indeed a pretty reliable way of storing data about other types of negotiations, as well. In fact, blockchain technology can be used to store data about feature exchanges, stops in a supply chain, and even votes for a candidate.

Virtuoso services network Deloitte recently surveyed 1,000 companies across seven states about integrating blockchain into their business operations. Their look into found that 34% already had a blockchain system in production today, while another 41% foresaw to deploy a blockchain application within the next 12 months. In beyond, nearly 40% of the surveyed companies reported they would initiate $5 million or more in blockchain in the coming year.

Here are some of the sundry popular applications of blockchain being explored today.

Banks: possibly no industry stands to benefit from integrating blockchain into its job operations more than banking. Financial institutions only manage during business hours, five days a week. That cruels if you try to deposit a check on Friday at 6 p.m., you likely will have to wait until Monday morning to see that well off hit your account. Even if you do make your deposit during commerce hours, the transaction can still take 1-3 days to verify due to the sheer tome of transactions that banks need to settle. Blockchain, on the other custody, never sleeps. By integrating blockchain into banks, consumers can see their annals processed in as little as 10 minutes, basically the time it takes to add a prevent a rough out to the blockchain, regardless of the time or day of the week. With blockchain, banks also suffer with the opportunity to exchange funds between institutions more quickly and securely. In the standard trading business, for example, the settlement and clearing process can take up to three epoches (or longer, if banks are trading internationally), meaning that the money and appropriations are frozen for that time. Given the size of the sums involved, unruffled the few days that the money is in transit can carry significant costs and risks for banks. Santander, a European bank, put the likely savings at $20 billion a year. Capgemini, a French consultancy, assesses that consumers could save up to $16 billion in banking and guarantee fees each year through blockchain-based applications.

Cryptocurrency: blockchain put ups the bedrock for cryptocurrencies like Bitcoin. As we explored earlier, currencies be partial to the U.S. dollar are regulated and verified by a central authority, usually a bank or authority. Under the central authority system, a user’s data and currency are technically at the whim of their bank or administration. If a user’s bank collapses or they live in a country with an tergiversating government, the value of their currency may be at risk. These are the worries out of which Bitcoin was borne. By spreading its men across a network of computers, blockchain allows Bitcoin and other cryptocurrencies to serve without the need for a central authority. This not only reduces danger but also eliminates many of the processing and transaction fees. It also give out withs those in countries with unstable currencies a more stable currency with various applications and a wider network of individuals and institutions they can do business with, both domestically and internationally (at trifling, this is the goal.)  

Healthcare: health care providers can leverage blockchain to securely store their patients’ medical records. When a medical record is moulded and signed, it can be written into the blockchain, which provides patients with the buttress and confidence that the record cannot be changed. These personal strength records could be encoded and stored on the blockchain with a private key, so that they are solely accessible by certain individuals, thereby ensuring privacy

Property Distances: if you have ever spent time in your local Recorder’s Place, you will know that the process of recording property rights is both cumbersome and inefficient. Today, a physical deed must be delivered to a government worker at the local recording office, where is it manually entered into the county’s medial database and public index. In the case of a property dispute, claims to the hallmark must be reconciled with the public index. This process is not good costly and time-consuming — it is also riddled with human error, where each inaccuracy perceives tracking property ownership less efficient. Blockchain has the potential to annihilate the need for scanning documents and tracking down physical files in a shire recording offices. If property ownership is stored and verified on the blockchain, proprietresses can trust that their deed is accurate and permanent.

Smart Compacts: a smart contract is a computer code that can be built into blockchain to further, verify, or negotiate a contract agreement. Smart contracts operate impaired a set of conditions that users agree to. When those conditions are met, the as regards of the agreement are automatically carried out. Say, for example, I’m renting you my apartment using a sharp contract. I agree to give you the door code to the apartment as soon as you pay me your care deposit. Both of us would send our portion of the deal to the smart narrow, which would hold onto and automatically exchange my door organization for your security deposit on the date of the rental. If I don’t supply the door practices by the rental date, the smart contract refunds your security drop. This eliminates the fees that typically accompany using a notary or third-party liaison.

Supply Chains: suppliers can use blockchain to record the origins of materials that they sooner a be wearing purchased. This would allow companies to verify the authenticity of their outcomes, along with health and ethics labels like “Organic,” “Regional,” and “Fair Trade.”

Voting: voting with blockchain carries the budding to eliminate election fraud and boost voter turnout, as was tested in the November 2018 midterm designations in West Virginia. Each vote would be stored as a block on the blockchain, traversing them nearly impossible to tamper with. The blockchain protocol force also maintain transparency in the electoral process, reducing the personnel fundamental to conduct an election, and provide officials with instant results.

Advantages of Blockchain

For all its complicatedness, blockchain’s potential as a decentralized form of record-keeping is almost without limit. From major user privacy and heightened security, to lower processing fees and fewer wrongdoings, blockchain technology may very well see applications beyond those thumbnail sketched above.

Here are the selling points of blockchain for businesses on the market today.

Loosely precision: transactions on the blockchain network are approved by a network of thousands or millions of computers. This liquidates almost all human involvement in the verification process, resulting in less benign error and a more accurate record of information. Even if a computer on the network were to insinuate a computational mistake, the error would only be made to one copy of the blockchain. In broken for that error to spread to the rest of the blockchain, it would need to be run by at least 51% of the network’s computers — a near impossibility.

Cost: typically, consumers pay a bank to testify to a transaction, a notary to sign a document, or a minister to perform a marriage. Blockchain slays the need for third-party verification and, with it, their associated costs. Company owners incur a small fee whenever they accept payments using faith cards, for example, because banks have to process those goings-on. Bitcoin, on the other hand, does not have a central authority and has for all practical purposes no transaction fees.

Decentralization: blockchain does not store any of its information in a median location. Instead, the blockchain is copied and spread across a network of computers. Whenever a new stumbling-block is added to the blockchain, every computer on the network updates its blockchain to mirror the change. By spreading that information across a network, rather than aggregating it in one central database, blockchain becomes more difficult to tamper with. If a reproduction of the blockchain fell into the hands of a hacker, only a single example of information, rather than the entire network, would be compromised.

Productivity: transactions placed through a central authority can take up to a few days to put down. If you attempt to deposit a check on Friday evening, for example, you may not actually see loots in your account until Monday morning. Whereas financial creations operate during business hours, five days a week, blockchain is fire up 24 hours a day, seven days a week. Transactions can be completed in almost ten minutes and can be considered secure after just a few hours. This is very useful for cross-border trades, which usually take much greater because of time-zone issues and the fact that all parties must reinforce payment processing.

Privacy: many blockchain networks operate as acknowledged databases, meaning that anyone with an internet connection can judge a list of the network’s transaction history. Although users can access names about transactions, they cannot access identifying information encircling the users making those transactions. It is a common misperception that blockchain networks like bitcoin are anonymous, when in fait accompli they are only confidential. That is, when a user makes catholic transactions, their unique code called a public key, is recorded on the blockchain, quite than their personal information. Although a person’s identity is alleviate linked to their blockchain address, this prevents hackers from seizing a user’s personal information, as can occur when a bank is hacked.

Asylum: once a transaction is recorded, its authenticity must be verified by the blockchain network. Thousands or settle millions of computers on the blockchain rush to confirm that the details of the obtain are correct. After a computer has validated the transaction, it is added to the blockchain in the anatomy of a block. Each block on the blockchain contains its own unique hash, along with the harmonious hash of the block before it. When the information on a block is edited in any way, that deterrent’s hash code changes — however, the hash code on the block after it inclination not. This discrepancy makes it extremely difficult for information on the blockchain to be silvered without notice.

Transparency: even though personal information on blockchain is kept GI Joe, the technology itself is almost always open source. That means that operators on the blockchain network can modify the code as they see fit, so long as they possess a majority of the network’s computational power backing them. Keeping evidence on the blockchain open source also makes tampering with evidence that much more difficult. With millions of computers on the blockchain network at any allowed time, for example, it is unlikely that anyone could make a modification without being noticed.

Challenges to Adopting Blockchain

While there are noteworthy upsides to the blockchain, there are also significant challenges to its adoption. The roadblocks to the commitment of blockchain technology today are not just technical. The real challenges are public and regulatory, for the most part, to say nothing of the thousands of hours (read: shin-plasters) of custom software design and back-end programming required to integrate blockchain to widespread business networks.  

Here are some of the challenges standing in the way of widespread blockchain adoption.

Rate: although blockchain can save users money on transaction fees, the technology is far from unasked for. The “proof of work” system that bitcoin uses to validate agreements, for example, consumes vast amounts of computational power. In the real world, the power from the millions of computers on the bitcoin network is penny-pinching to what Denmark consumes annually. All of that energy costs currency and according to a recent study from research company Elite Accessories, the cost of mining a single bitcoin varies drastically by location, from equitable $531 to a staggering $26,170. Based on average utility costs in the Pooled States, that figure is closer to $4,758. Despite the costs of drawing bitcoin, users continue to drive up their electricity bills in codify to validate transactions on the blockchain. That’s because when miners add a sketch to the bitcoin blockchain, they are rewarded with enough bitcoin to vamoose their time and energy worthwhile. When it comes to blockchains that do not use cryptocurrency, manner, miners will need to be paid or otherwise incentivized to validate acta.

Inefficiency: bitcoin is a perfect case study for the possible inefficiencies of blockchain. Bitcoin’s “documentation of work” system takes about ten minutes to add a new block to the blockchain. At that rank, it’s estimated that the blockchain network can only manage seven acta per second (TPS). Although other cryptocurrencies like Ethereum (20 TPS) and Bitcoin Lolly (60 TPS) perform better than bitcoin, they are still restricted by blockchain. Legacy brand Visa, for context, can process 24,000 TPS.

Secrecy: while confidentiality on the blockchain network protects users from hacks and game reserves privacy,  it also allows for illegal trading and activity on the blockchain network. The most cited warning of blockchain being used for illicit transactions is probably Silk Course, an online “dark web” marketplace operating from February 2011 until October 2013 when it was shut down down by the FBI. The website allowed users to browse the website without being lose sight of and make illegal purchases in bitcoins. Current U.S. regulation prevents drugs of online exchanges, like those built on blockchain, from unqualified anonymity. In the United States, online exchanges must obtain communication about their customers when they open an account, prove the identity of each customer, and confirm that customers do not appear on any inclination of known or suspected terrorist organizations.

Security: several central banks, embodying the Federal Reserve, the Bank of Canada and the Bank of England, have slung investigations into digital currencies. According to a February 2015 Bank of England scrutiny report, “Further research would also be required to devise a organization which could utilize distributed ledger technology without compromising a medial bank’s ability to control its currency and secure the system against systemic condemn.”

Susceptibility: newer cryptocurrencies and blockchain networks are susceptible to 51% attacks. These begins are extremely difficult to execute due to the computational power required to gain preponderance control of a blockchain network, but NYU computer science researcher Joseph Bonneau asserted that might change. Bonneau released a report last year estimating that 51% criticisms were likely to increase, as hackers can now simply rent computational power, to a certain extent than buying all of the equipment.

Blockchain: Final Thoughts

First proposed as a experiment with project in 1991, blockchain technology is comfortably settling into its up to the minute twenties. Like most millennials settling into their time twenties, blockchain has seen its fair share of public scrutiny past the last two decades, with businesses around the world speculating all round what the technology is capable of and where it’s headed in the years to come.

With various practical applications for the technology already being implemented and explored, blockchain is in the end making a name for itself at age twenty-seven — in no small part because of bitcoin and cryptocurrency. As a buzzword on the idiom of every investor in the nation, blockchain stands to make business and regulation operations more accurate, efficient, and secure.

As we prepare to head into the third decade of blockchain, it’s no longer a harbour of if legacy companies will catch on to the technology. It’s a matter of when.

‘Blockchain, Described’

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