Thursday 21 June 2018

What is blockchain? The most disruptive tech in decades.

The distributed ledger technology, better known as blockchain, has the potential to eliminate huge amounts of record-keeping, save money and disrupt IT in ways not seen since the internet arrived.

What is blockchain?

First and foremost, Blockchain is a public electronic ledger that can be openly shared among disparate users and that creates an unchangeable record of their transactions, each one time-stamped and linked to the previous one. Each digital record or transaction in the thread is called a block (hence the name), and it allows either an open or controlled set of users to participate in the electronic ledger. Each block is linked to a specific participant.
Blockchain can only be updated by consensus between participants in the system, and when new data is entered, it can never be erased. The blockchain contains a true and verifiable record of each and every transaction ever made in the system.
In layman's terms, blockchain is a write-once, append-many electronic ledger.
Blockchain isn't a single technology. Rather it's an architecture that allows disparate users to make transactions and then creates an unchangeable record of those transactions.
Blockchain Forrester Research
Blockchain isn't a single technology. Rather it's an architecture that allows disparate users to make transactions and then creates an unchangeable, secure record of those transactions.
While it has great potential, blockchain technology is in its infancy and CIOs and their business counterparts should expect setbacks in deploying the technology, including the real possibility of serious bugs in the software used atop blockchain to create business-specific applications – for example, a mobile payments system.
In another example, one of the most prevalent blockchain platforms, Ethereum, doesn't support the use of decimal points in its script for smart (self executing) contracts. Those coding a blockchain network would need to create a workaround.
The Linux Foundation has created tools for building out blockchain collaboration networks. And in July, the open-source developer unveiled Hyperledger Fabric 1.0, a collaboration tool for building blockchain distributed ledger business networks, such as smart contracts.
While some industry groups are working toward standardizing versions of blockchain software, there are also about 200 startups working on their own versions of the distributed ledger technology.
Why is blockchain getting so much buzz? In a word, Bitcoin. Bitcoin is the wildly hyped cryptocurrency, a method of transacting payments over an open network using digital bits and encryption. It was the first ever decentralized one when it was created in 2009. Other forms of cryptocurrency or virtual money, such as Ether (based on the Ethereum blockchain application platform), have also sprung up and have opened new venues for cross-border monetary exchanges.
The term bitcoin was first... well, coined in 2008 when Satoshi Nakamoto (likely a pseudonym for one or more developers) wrote a paper about a "peer-to-peer version of electronic cash that would allow online payments to be sent directly from one party to another without going through a financial institution."

What does blockchain do?

As a peer-to-peer network, combined with a distributed time-stamping server, blockchain ledgers can be managed autonomously to exchange information between disparate parties. There's no need for an administrator. In effect, the blockchain users are the administrator.
Additionally, blockchain networks can be used for "smart contracts," or scripts that automatically execute when certain conditions are met. For example, Ethereum Ether exchange users must meet pre-determined conditions that prove someone owns the cryptocurrency and have authority to send the money they claim to own. In addition, multiple blockchain users can create contracts that require more than one set of inputs to trigger a transaction.
One example: real estate transactions require sign offs between buyers, sellers and their financial institutions.
blockchain how it works Network World
Each digital record or transaction in the electronic ledger is called a block. When a block is completed, it creates a unique secure code that ties it to the next block.

How secure is blockchain?

While no system is "unhackable," blockchain's simple topology is the most secure today, according to Alex Tapscott, the CEO and founder of Northwest Passage Ventures, a venture capital firm that invests in blockchain technology companies.
"In order to move anything of value over any kind of blockchain, the network [of nodes] must first agree that that transaction is valid, which means no single entity can go in and say one way or the other whether or not a transaction happened," Tapscott said. "To hack it, you wouldn't just have to hack one system like in a bank..., you'd have to hack every single computer on that network, which is fighting against you doing that."
The computing resources of most blockchains are tremendous, Tapscott said, because it's not just one computer but many. For example, the Bitcoin blockchain harnesses anywhere between 10 and 100 times as much computing power compared to all of Google's serving farms put together.
Blockchain Forrester Research
As with any emerging technology, blockchain faces challenges and barriers to adoption.
"So again, [it's] not un-hackable, but significantly better than anything we've come up with today," Tapscott said.

Public vs. private blockchains

There are a variety of blockchain permutations, and they fall mainly into one of two categories - public or private. Public blockchains allow anyone to see or send transactions as long as they're part of the consensus process. There are also consortium blockchains, where only a pre-selected number of nodes are authorized to use the ledger. For example, a group of banks and their clearinghouse might use blockchain as part of the trade-clearing, where each node is associated with a step in the verification process.
Private blockchains, in contrast, restrict the ability to write to a distributed ledger to one organization, such as a group of employees within a corporation, or between a set number of organizations, such as a number of banks that agree to a network partnership.
Along the way, blockchain - because of its self-policing security - eliminates huge amounts of record keeping, which can get very confusing when multiple parties are involved in a transaction, according to Saurabh Gupta, vice president of strategy at IT services company Genpact.

Which industries use blockchain?

Shipping. Fintech. Healthcare, Energy. Blockchains are being put to a wide variety of uses in several industries. (Most recently it's been touted as a way to exchange carbon credits.)
In shipping, for example, a bill of lading for cargo shipments has traditionally been paper based, which requires multiple sign-offs by inspectors and receivers before goods can be delivered. Even when the system is electronic, it still requires multiple parties to sign off on cargo shipments, creating a lengthy administrative process. To try and streamline that cumbersome process, the world's largest container shipment operator, Maersk, in March 2017 announced it is using a blockchain-based ledger to manage and track the paper trail of tens of millions of shipping containers by digitizing the supply chain. And Maersk has now teamed up with IBM on a new blockchain-based electronic shipping platform. It’s expected to be up and running later in 2018.
[ Further reading: Blockchain breaks out in the enterprise ]
Each participant in the shipping supply chain can view the progress of goods through the blockchain ledger, understanding where a container is in transit. They can also see the status of customs documents, or view bills of lading and other data in real time. And, because it creates an immutable record, no one party can modify, delete or even append any one of the blocks without the consensus from others on the network.
"Blockchain and distributed ledgers may eventually be the method for integrating the entire commercial world's record keeping," Gupta said.
Genpact, for example, announced a service for finance and accounting that leverages blockchain-based smart contracts to capture all terms and conditions between a customer and an organization for an order.

Blockchain in FinTech

But it's financial services technology where blockchain is currently shining brightly.
At a high level, blockchain removes third parties from the transaction equation; in other words, a financial transaction on a blockchain needs no bank or government backer, and that means no fees.
Because blockchain entries can be seen in real time, the technology also has the potential to reduce time for clearance and settlement, which can take up to five days.
Accenture recently released a report claiming blockchain technology could reduce infrastructure costs for eight of the world's 10 largest investment banks by an average of 30%, "translating to $8 billion to $12 billion in annual cost savings for those banks."
In the case of cross-border payments, processing is often complex and includes multiple layers of communication among payment participants to verify transactions - an operation known as payment and settlement.
Payments, clearance and settlement in the financial services industry - including stock markets - is rife with inefficiencies because each organization in the process maintains its own data and must communicate with the others through electronic messaging about where it is in the process. As a result, settlements typically take two days. Those delays in settlements force banks to set aside money that could otherwise be invested.
Because it can instantly share data with each organization involved in a blockchain database or ledger, the technology reduces or eliminates the need for reconciliation, confirmation and trade break analysis. That helps yield a more efficient and effective clearance and settlement process, according to Accenture.

Source :https://www.computerworld.com/article/3191077/security/what-is-blockchain-the-most-disruptive-tech-in-decades.html

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