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Related to blockchain: Bitcoin


The underlying architecture of Bitcoin and other financial systems. The blockchain is a distributed ledger that provides verifiable proof of a transaction between two parties. There is no central repository. The blockchain is continuously updated and replicated on many nodes dedicated to that platform.

Using Bitcoin as the example, blocks of transactions are created when parties exchange coins, one block approximately every 10 minutes. All the blocks are linked (see illustration below). By using public/private key pairs, only Bitcoin owners can transfer their coins, but the authenticity of the transactions can be verified by anyone. The date and amount of coins transferred are transparent but not the parties involved in the transaction. See public key cryptography.

Not Just for Bitcoin
Because the blockchain algorithm provides a robust list of rightful ownership, both the public and private sectors are using or exploring blockchain technologies for digital currencies other than Bitcoin as well as applications such as contracts, fundraising and title registration. By recording transactions without a middleman, performance is improved, and not having a central point of attack means greater security. In addition, transactions cannot be reversed or altered. As a trusted protocol, proponents claim that blockchain systems will eventually revolutionize every aspect of the financial world. See ICO, Bitcoin mining, Bitcoin, Litecoin and Ethereum.

The Blockchain - One-Way Linkage
Blocks are chained together by storing the hash of the header of the previous block. This prevents transactions from being modified or refuted. If a transaction within a block were altered, the link to the subsequent block would be broken. The Merkle root is a hashed summary of transactions that is used for quick verification (see Merkle tree). See cryptographic hash function.
References in periodicals archive ?
Microsoft's whitepaper offers several policy recommendations applicable to both blockchain users and their regulators.
This group imagines that blockchain and cryptos are the solution to every problem in the world.
The verification of blockchain records is called 'mining'.
In reality, blockchain is one of the mostoverhyped technologies ever.
The laboratory also has the goal of popularising blockchain and providing assistance in the preparation of educational programmes in this area.
Blockchain investment propositions routinely make wild promises to overthrow entire industries, such as cloud computing, without acknowledging the technology's obvious limitations.
A myriad of government and private sector investment and blockchain specialists are expected to attend the seminar.
Now, preparation for blockchain technology in Korea is smoothly underway focusing on the banking sector, as leading domestic banks work together to develop a payment system that will allow the existing Korean won to be transacted into other currencies via blockchain.
Secondly, blockchain eliminates the need for banks to act as intermediaries.
In a statement, PLDT said it joined the Carrier Blockchain Study Group (CBSG), the global blockchain consortium of telecom carriers led by Japan's Softbank Corp, US-based Sprint Corp.
M2 EQUITYBITES-February 26, 2018-Red Violet Acquires 5% Interest in Dragonchain Blockchain Tech Company
CBSG was launched in September 2017 to enable the joint development of an innovative blockchain platform designed specifically for telecom carriers, led by Japan-based SoftBank Corp.